ArticlePDF Available

The association of gene polymorphisms with the muscle fibre type composition [in Russian]

Authors:
Ildus I. Ahmetov at Liverpool John Moores University
Ildus I. Ahmetov
I V Astratenkova
I V Astratenkova
I V Astratenkova
  • This person is not on ResearchGate, or hasn't claimed this research yet.
A M Druzhevskaia
A M Druzhevskaia
A M Druzhevskaia
  • This person is not on ResearchGate, or hasn't claimed this research yet.
A I Komkova
A I Komkova
A I Komkova
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Show all 8 authorsHide
Download full-text PDF
Read full-text
Download citation

Abstract

Muscle fiber composition of m. vastus lateralis has significant individual variability mainly depending on genetic factors. Present study shows analysis of association between polymorphisms of three muscle performance-related genes and muscle fiber type composition in 48 young healthy men. DNA was obtained from mouthwash samples by alkaline extraction. Polymorphism determination of PPARalpha, ACE and ACTN3 genes was performed using polymerase chain raction. Muscle fiber typing from m. vastus lateralis was performed using immunohistochemistry method. We found an association of increased frequency of intron 7 G allele of PPARalpha gene (93.9% vs 60.0%) and D allele of ACE gene (68.8% vs 34.4%) in the group with the highest proportion of slow-twitch fibers (56-70%) compared to the group with the lowest proportion (25-43%). Thus, PPARalpha and ACE genes can be considered as potential candidate genes for muscle fiber type determination.
Content uploaded by Ildus I. Ahmetov
Author content
All content in this area was uploaded by Ildus I. Ahmetov
Content may be subject to copyright.
883
РОССИЙСКИЙ ФИЗИОЛОГИЧЕСКИЙ ЖУРНАЛ им. И. М. СЕЧЕНОВА
RUSSIAN JOURNAL OF PHYSIOLOGY
(formerly I.M. Sechenov Physiological Journal)
92 · N 7 · 2006
АССОЦИАЦИЯ ПОЛИМОРФИЗМОВ ГЕНОВ С ТИПОМ МЫШЕЧНЫХ ВОЛОКОН
© И.И. Ахметов,
1*
И.В. Астратенкова,
1
А.М. Дружевская,
1
А.И Комкова,
1
Е.В. Любаева,
2
П.П.
Таракин,
2
Б.С. Шенкман,
2
В.А. Рогозкин.
1
1
Санкт-Петербургский НИИ физической культуры, Санкт-Петербург, 197110.
2
ГНЦ РФ Институт медико-биологических проблем РАН, Москва, 123007.
*
E-mail: contact@genoterra.ru
Состав мышечных волокон в m. vastus lateralis имеет огромные индивидуальные различия,
зависящие главным образом от генетических факторов. Нами представлен анализ ассоциации
ранее связанных с мышечной деятельностью полиморфизмов 3 генов с типом мышечных воло-
кон у 48 здоровых физически активных молодых мужчин. ДНК выделяли методом щелочной
экстракции из клеток буккального эпителия. Полиморфизм генов PPARα, ACE и
ACTN3 выяв-
ляли с использованием полимеразной цепной реакции. Состав мышечных волокон определяли с
помощью иммуногистохимического анализа мышечной ткани из m. vastus lateralis. При сравне-
нии двух групп людей с пониженным (25-43%) и повышенным (56-70%) содержанием медлен-
ных мышечных волокон, во второй группе было выявлено достоверное преобладание носителей
аллелей G по гену PPARα (93,3% против 60,0%) и D по гену ACE (68,8% против 34,4%). Таким
образом, гены PPARα и ACE могут быть отнесены к генам-кандидатам, детерминирующим со-
став мышечных волокон.
Ключевые слова: мышечные волокна, иммуногистохимия, биопсия, ген, полиморфизм.
Рос. физиол. журн. им. И. М. Сеченова. Т.92. № 7. С. 883-888. 2006.
I.I. Ahmetov,
1
I.V. Astratenkova,
1
A.M. Druzhevskaya,
1
A.I. Komkova,
1
E.V. Lyubaeva,
2
P.P. Ta-
rakin,
2
B.S. Shenkman,
2
V.A. Rogozkin.
1
THE ASSOCIATION OF GENE POLYMORPHISMS WITH
THE MUSCLE FIBER TYPE COMPOSITION.
1
St Petersburg Research Institute of Physical Culture,
St Petersburg, 197110;
2
Institute for Biomedical Problems of the Russian Acad. Sci., Moscow,
123007.
Muscle fiber composition of m. vastus lateralis has great individual variability, mainly depend-
ing on genetic factors. Present study shows analysis of association between polymorphisms of three
muscle performance related genes and muscle fiber type composition in 48 young healthy men. DNA
was obtained from mouthwash samples by alkaline extraction. Polymorphism determination of
PPARα, ACE and ACTN3 genes was performed using polymerase
chain reaction. Muscle fiber typing
from m. vastus lateralis was performed using immunohistochemistry method. We found an association
of increased frequency of intron 7 G allele of PPARα gene (93,9% vs 60,0%) and D allele of ACE
gene (68,8% vs 34,4%) in the group with the highest proportion of slow-twitch fibers (56-70%) com-
pared to the group with the lowest proportion (25-43%). Thus, PPARα and ACE genes can be consi-
dered as potential candidate genes for muscle fiber type determination.
Keywords: muscle fibers, immunohistochemistry, biopsy, gene, polymorphism.
RUSSIAN PHYSIOLOGICAL JOURNAL, V. 92, N 7, P. 883-888. 2006
884
Скелетные мышцы человека состоят из трех основных типов мышечных волокон, которые
различаются по сократительным и метаболическим характеристикам – волокна I (медленные),
IIa (промежуточные) и IId/x (быстрые) типов. Ключевым признаком, определяющим тип мы-
шечного волокна, является молекулярная организация миозина. На различном сродстве моно-
клональных антител к тяжелым цепям миозина (ТЦМ) разного типа основан метод иммуноги-
стохимического анализа биоптатов мышечной ткани для определения соотношения быстрых и
медленных волокон [1].
В латеральной головке четырехглавой мышцы бедра человека (m. vastus lateralis) обнару-
жена высокая степень вариабельности соотношения мышечных волокон (для медленных воло-
кон от 5 до 90%), что свидетельствует о значительном вкладе генетических факторов в детер-
минацию состава мышечных волокон.
В связи с этим, изучение полиморфизма генов и их ассоциаций с формированием, разви-
тием и трансформацией мышечных волокон имеет большое значение не только для фундамен-
тальных, но и научно-прикладных исследований. В практическом плане определение состава
мышечных волокон важно для правильного составления методики физической тренировки и
выбора тактики лечения больных с различными повреждениями опорно-двигательного аппара-
та, наследственными миопатическими заболеваниями и метаболическими расстройствами. Од-
нако наиболее информативные методы определения состава мышечных волокон с использова-
нием биопсийного материала мышечной ткани малодоступны, ограничены в распространении и
весьма затратны. В качестве альтернативного метода представляется довольно перспективным
направлением косвенная оценка состава мышечных волокон на основе изучения полиморфиз-
мов генов, связанных с мышечной деятельностью. К таким генам, например, можно отнести ген
α рецептора, активируемого пролифераторами пероксисом (PPARα), ген ангиотензин-
превращающего фермента (ACE) и ген α-актинина-3 (ACTN3).
Существует ряд работ по ассоциации аллелей D гена ACE и R гена ACTN3 с повышенны-
ми скоростно-силовыми качествами в различных группах людей [6,8]. Это связано с тем, что D
аллель имеет свойство повышать уровень и активность ангиотензин-превращающего фермента,
что приводит к увеличению содержания фактора роста – ангиотензина II. Гомозиготы по му-
тантному аллелю Х гена ACTN3 лишены белка альфа-актинина-3, который содержится исклю-
чительно в быстрых мышечных волокнах. Альфа-актинин-3 является структурным компонен-
том Z-дисков миофибрилл и кроме статической функции выполняет регуляторную функцию,
принимая участие в регуляции дифференциации и сокращении миофибрилл. С другой стороны
I аллель гена ACE ассоциируется с проявлением повышенной выносливости из-за сосудорас-
ширяющего эффекта.
Ген PPARα входит в семейство ядерных рецепторов и регулирует экспрессию несколько
десятков генов, вовлеченных в обмен жиров и углеводов. У носителей G аллеля окисление
жирных кислот в печени, миокарде, скелетных мышцах и других органах происходит намного
интенсивнее, чем у носителей С аллеля. Недостаток окисления жирных кислот у носителей С
аллеля компенсируется повышением утилизации глюкозы [4]. Анализ этих данных позволил
высказать предположение, что носители генотипов по ACE, ACTN3 и PPARα могут иметь раз-
личное соотношение быстрых и медленных мышечных волокон в скелетных мышцах человека.
Для проверки этой гипотезы изучали распределение частот генотипов и аллелей трех генов в
группе здоровых мужчин.
Цель настоящего исследования - определение ассоциации G/C полиморфизма 7 интрона
гена PPARα, I/D полиморфизма гена ACE и R577X полиморфизма гена ACTN3 с составом мы-
шечных волокон здоровых, молодых мужчин.
МЕТОДИКА
В исследовании приняли участие 48 здоровых физически активных молодых мужчин (воз-
раст – 22 ± 0,4 года, вес – 72,8 ± 1,5 кг, рост – 179,1 ± 0,9 см). Испытуемые были предупрежде-
ны об условиях эксперимента и дали письменное соглашение на добровольное участие в нем.
885
Эксперимент был одобрен Физиологической секцией Российской Национальной комиссии по
биологической этике. Забор биологического материала для генетического анализа проводили с
помощью смыва буккальных клеток из ротовой полости физиологическим раствором. ДНК вы-
деляли методом щелочной экстракции [2]. Полиморфизм генов определяли с использованием
метода полимеразной цепной реакции (ПЦР). Для амплификации фрагментов генов PPARα,
ACE и ACTN3 использовали двухпраймерную систему (для PPARα: прямой праймер (п.п.) –
ACAATCACTCCTTAAATATggTgg, обратный праймер (о.п.) -
AAgTAgggACAgACAggACCAgTA; для ACE: п.п. – CTggAgACCACTCCCATCCTTTCT, о.п. -
ATgTggCCATCACATTCgTCAgAT; для ACTN3: п.п. – CTgTTgCCTgTggTAAgTggg, о.п. -
TggTCACAgTATgCAggAggg). В дальнейшем, продукты ПЦР генов PPARα и ACTN3 были
подвергнуты специфическому рестрикционному анализу с использованием эндонуклеаз рест-
рикции Taq I и Bst DEI (СибЭнзим, Новосибирск), соответственно. Ампликоны генов ACE, а
также продукты рестрикции остальных генов разделяли с помощью вертикального электрофо-
реза, и после окрашивания полиакриламидного геля этидием бромида визуализировали с ис-
пользованием трансиллюминатора. Более подробно методы по определению полиморфизмов
генов PPARα, ACE и ACTN3 описаны в работах Flavell и соавт. [3], Rigat и соавт. [7] и Mills и
соавт. [5].
Для определения состава мышечных волокон, предварительно из m. vastus lateralis (под
местной анестезией 1% раствором лидокаина) методом игольчатой биопсии по Бергстрему бра-
ли пробы мышечной ткани и замораживали в жидком азоте. Серийные поперечные срезы тол-
щиной 10 μm готовили в криостате при -20 ºС и монтировали на предметные стекла. Для имму-
ногистохимического выявления изоформ ТЦМ использовали иммунопероксидазную технику.
Применяли антитела против медленных (MHCs) и быстрых (MHCf) цепей миозина (клоны
NCL-MHCs и NCL-MHCf (а+в) (Novocastra Laboratories)). Срезы, которые инкубировали без
первичных антител, использовали как контроль для выявления неспецифической окраски. Для
усиления метки антиген-антитело был использован Vectrastain ABC kit (Vector Labs, CA), кото-
рый визуализировался диаминобензидин пероксидазной реакцией. Распределение волокон вы-
ражали как соотношение между числом волокон каждого типа на срезе к общему количеству
волокон. Измеряли все волокна (200-300 волокон) на каждом срезе. Площадь поперечного се-
чения (ППС) измеряли не менее чем у 100 волокон каждого типа с помощью системы анализа
изображений QUANTIMET-500 (Leica) с цветной цифровой видеокамерой JVC TK-1280E. Все
сравниваемые срезы готовили и окрашивали одновременно реагентами фирмы Sigma (USA).
Статистическую обработку полученных результатов проводили с использованием методов
общей статистики и корреляционного анализа. Вычисляли среднее значение показателя и
ошибку среднего. Оценка достоверности проводилась по t-критерию Стьюдента. Различия счи-
тались достоверными при значении P<0.05.
РЕЗУЛЬТАТЫ ИССЛЕДОВАНИЯ И ИХ ОБСУЖДЕНИЕ
Анализ частоты распределения генотипов по гену PPARα у мужчин показал, что к гено-
типу GG относятся 62,5%, к генотипу GC 27,1% и к генотипу CC 10,4%. Для генотипов II, ID и
DD по гену ACE эти величины составили 31,25%, 37,5% и 31,25%. Для генотипов RR, RX и XX
по гену ACTN3 они были 37,5%, 62,7% и 0%.
В результате проведенного анализа выявлено, что наибольшее преобладание медленных
волокон соответствует генотипам: DD по ACE (56,6±2,5%), GG по PPARα (53,5±2,4%) и RX по
ACTN3 (53±2,5%), а наименьшее – генотипам СС по PPARα (38,7±2,4%), II по ACE (45,9±3%) и
RR по ACTN3 (51,7±3,9%).
В дальнейшем обследуемые были разделены на 3 равные группы по
16 человек с высоким,
средним и низким содержанием медленных или быстрых мышечных волокон. Это позволило
обнаружить достоверные различия в частоте встречаемости аллелей генов PPARα и ACE между
группами с крайними значениями. Так, в группе с высоким содержанием медленных волокон
(от 55,7% до 69,3%) преобладали носители аллелей G по PPARα (93,3%) и D по ACE (68,8%) по
886
сравнению с группой, лица которых содержали низкий процент (от 24,7% до 43%) медленных
мышечных волокон (60% носителей аллеля G и 34,4% носителей аллеля D; P<0.05) (Табл. 1).
Таблица 1
Распределение частот аллелей генов PPARα, ACE и ACTN3
в группах мужчин с различным содержанием медленных мышечных волокон.
Группы с содержанием
медленных волокон, %
n
Ген PPARα Ген АСЕ Ген ACTN3
G аллель, % D аллель, % X аллель, %
24,7 – 43 (группа 1М) 16 60,0 34,4 31,3
45-53,9 (группа 2М) 16 76,9 46,9 33,3
55,7-69,3 (группа 3М) 16 93,3* 68,8* 30,7
Примечание. *Достоверные различия по t-критерию Стьюдента между 1М и 3М группами (P<0.05).
При распределении обследуемых на группы с разными показателями процентного соот-
ношения быстрых мышечных волокон была выявлена ассоциация С аллеля гена PPARα и I ал-
леля гена ACE с повышенным содержанием быстрых мышечных волокон (P<0.05). Несмотря на
некоторое преобладание частоты аллеля R по гену ACTN3 (77,8%) у лиц с высоким содержани-
ем быстрых мышечных волокон по сравнению с группой с низким содержанием таких волокон
(частота аллеля R 63,6%) различия между ними оказались статистически недостоверными
(Табл. 2).
При анализе ассоциации генотипов с площадью поперечного сечения быстрых или мед-
ленных мышечных волокон достоверных отличий обнаружено не было. Установлено, что наи-
большая ППС медленных волокон была выявлена у носителей генотипов GG по PPARα
(5396±236 мкм
2
) и DD по ACE (5513±344 мкм
2
); наименьшая – у носителей генотипов СС по
PPARα (4953±494 мкм
2
) и II по ACE (4972±246 мкм
2
). Кроме того, наибольшие показатели ППС
быстрых мышечных волокон были обнаружены у носителей генотипов GC по PPARα (6060±667
мкм
2
) и DD по ACE (6061±397 мкм
2
).
Таким образом, гипотеза о возможном наличии ассоциации между генотипами генов и со-
отношением быстрых и медленных мышечных волокон была подтверждена относительно генов
PPARα и ACE. С аллель гена PPARα имеет свойство понижать активность гена, что приводит к
увеличению утилизации глюкозы и уменьшению окисления жиров. К такому метаболизму бо-
лее предрасположены промежуточные
и быстрые мышечные волокна, что подтверждается
большим процентом быстрых волокон у носителей аллеля С. Кроме того, было выявлено, что
переходе от генотипа СС к генотипу GG увеличивается площадь медленных мышечных воло-
кон. Возможно, это связано с увеличением объема цитоплазмы, что определяется более высо-
ким окислительным потенциалом генотипа GG по сравнению с генотипами GC
и СС.
Таблица 2
Распределение частот аллелей генов PPARα, ACE и ACTN3
в группах мужчин с различным содержанием быстрых мышечных волокон
Группы с содержанием
быстрых волокон, %
n
Ген PPARα Ген АСЕ Ген ACTN3
С аллель, % I аллель, % R аллель, %
30-45 (группа 1Б) 16 9,6 31,2 63,6
45,1-58 (группа 2Б) 16 25,0 53,1 65,0
58,1-80 (группа 3Б) 16 37,7* 65,6* 77,8
Примечание. *Достоверные различия по t-критерию Стьюдента между 1Б и 3Б группами (P<0.05).
887
Ассоциация аллеля D по гену ACE с преобладанием медленных мышечных волокон, убе-
ждает в необходимости комплексного подхода при изучении ассоциаций полиморфизмов генов
с мышечной деятельностью. Надо отметить, что I/D полиморфизм гена ACE не связан с пере-
ключением одного вида метаболизма на другой, как это обнаружено в G/C полиморфизме гена
PPARα, а влияет только на концентрацию и активность одного ангиотензин-превращающего
фермента. В конечном итоге фенотипическое проявление I/D полиморфизма гена ACE зависит
от полиморфизмов других генов ренин-ангиотензиновой и каллекреин-кининовой систем. Воз-
можно, в нашем исследовании эффект аллеля I гена ACE был подавлен другими аллелями с ан-
тагонистическими свойствами, такими как С аллель гена PPARα. Тем не менее, у
носителей ал-
леля D отмечалась большая ППС быстрых и медленных мышечных волокон по сравнению с но-
сителями аллеля I, что указывает на сохранение гипертрофического эффекта аллеля D. При ис-
следовании ассоциации полиморфизма гена ACTN3 с содержанием быстрых и медленных мы-
шечных волокон не выявлено достоверных различий в частотах распределения генотипов RR,
RX и XX.
Представленные данные показывают
, что из трех изученных полиморфизмов к генам-
кандидатам, детерминирующим состав мышечных волокон могут быть отнесены гены PPARα и
ACE.
В заключение следует подчеркнуть, что состав мышечных волокон жестко детерминиро-
ван и изменяется незначительно в процессе систематического воздействия внешних стимулов.
Дальнейшие поиски генов, участвующих в формировании и развитии мышечных волокон, оче-
видно, следует вести с учетом экспериментальных данных, полученных в последнее время в
моделях на животных, при изучении процесса трансформации мышечных волокон.
Кроме того, необходимо проводить исследования по определению комплексного влияния
полиморфизмов генов на степень трансформации и гипертрофии мышечных волокон при сис-
тематическом воздействии различных внешних стимулов и, в том числе физических нагрузок.
СПИСОК ЛИТЕРАТУРЫ
1. Шенкман Б.С., Нетреба А.И., Литвинова К.С., Таракин П.П., Вихлянцев И.М., Подлубная
З.А., Немировская Т.Л., Ковалева М.А., Стеханова Т.Н., Попов Д.В., Виноградова О.Л.
Креатин как метаболический модулятор функции мышц человека в условиях силовой
тренировки. Сборник статей. Медико-биологические технологии повышения работоспо-
собности в условиях напряженных физических нагрузок. 102-116. 2004.
2. Bolla M.K., Haddad L., Humphries S.E., Winder A.F., Day I.N.M. A method of determination
of hundreds of APOE genotypes utilizing highly simplified, optimized protocols and restriction
digestion analysis by microtitre array diagonal gel electrophoresis (MADGE). Clin Chem. 41:
1599-1604. 1995.
3. Flavell D.M., Jamshidi Y., Hawe E., Torra I.P., Taskinen M.R., Frick M.H., Nieminen M.S.,
Kesaniemi Y.A., Pasternack A., Staels B., Miller G., Humphries S.E., Talmud P.J., Syvanne M.
Peroxisome proliferator-activated receptor α gene variants influence progression of coronary
atherosclerosis and risk of coronary artery disease. Circulation. 105: 1440 –1445. 2002.
4. Jamshidi Y., Montgomery H.E., Hense H-W., Myerson S.G., Torra I.P., Staels B., World M.J.,
Doering A., Erdmann J., Hengstenberg C., Humphries S.E., Schunkert H., Flavell D.M. Peroxi-
some proliferator-activated receptor α gene regulates left ventricular growth in response to ex-
ercise and hypertension. Circulation. 105: 950-955. 2002.
5. Mills M., Yang N., Weinberger R., Vander Woude D.L., Beggs A.H., Easteal S., North K. Diffe-
rential expression of the actin-binding proteins, alpha-actinin-2 and -3, in different species: im-
plications for the evolution of functional redundancy. Hum Mol Genet.10 (13): 1335-46. 2001.
888
6. Nazarov I.B., Woods D.R., Montgomery H.E., Shneider O.V., Kazakov V.I., Tomilin N.V.,
Rogozkin V.A. The angiotensin converting enzyme I/D polymorphism in Russian athletes. Eur
J Hum Genet. 9 (10): 797-801. 2001.
7. Rigat B., Hubert C., Corvol P., Soubrier F. PCR detection of the insertion/deletion polymor-
phism of the human angiotensin converting enzyme gene (DCP1) (dipeptidyl carboxypeptidase
1). Nucleic Acids Res. 20: 1433. 1992.
8. Yang N., MacArthur D.G., Gulbin J.P., Hahn A.G., Beggs A.H., Easteal S., North K. ACTN3
genotype is associated with human elite athletic performance. Am J Hum Genet. 73 (3): 627-
31. 2003.
Поступила 25 VII 2005
После обработки 13 XII 2005
© GenoTerra Ахметов И.И., Астратенкова
И.В., Дружевская
А.М., Комкова А.И., Любаева Е.В., Таракин П.П.,
Шенкман Б.С., Рогозкин
В.А. Ассоциация полиморфизмов генов с типом мышечных волокон // Рос. физиол. журн.
им. И.М. Сеченова. – 2006. – Т.92. - №7. – С.883-888.
*E-mail: contact@genoterra.ru
... The analysis of muscle fiber composition in 40 young men revealed higher percentage of slow-twitch fibers in 7G homozygotes compared to 7C homozygotes [15], although a statistical significance could not be reached due to a low frequency of 7C/7C genotypes (n = 4). In another study PPARA intron 7 G/C variant along with ACE I/D variant were found to be the strongest predictors for muscle fiber type determination [16]. Group of Ahmetov et al. [17] included 7G allele of PPARA gene among ten ''endurance alleles'' whose number positively correlated with the proportion of slow-twitch muscle fibers, and with maximal oxygen consumption. ...
... Under the circumstances it is possible that during intense exercise 7C carriers are more prone to rely on anaerobic processes what may be an adaptive stimulus leading to muscle fiber transformation. A muscle fiber composition have not been monitored in our study, but at least two studies associated PPARA 7 G/C genotypes with a muscle fiber specific composition in athletes [15,16]. Whilst initial composition is likely to be strongly influenced by genetic factors, training has significant effects on fiber shifts and related muscle metabolism changes. ...
Erratum: PPARA intron polymorphism associated with power performance in 30-s anaerobic wingate test (PLoS ONE (2015) 9:9 (e107171) Doi:10.1371/journal.pone.0107171)
Article
Full-text available
The second author’s name is spelled incorrectly. The correct name is: Petr Stastny. The correct citation is: Petr M, Stastny P, Pecha O, Steffl M, Seda O, Kohlikova E (2014) PPARA Intron Polymorphism Associated with Power Performance in 30-s Anaerobic Wingate Test. PLoS ONE 9(9): e107171. doi:10.1371/journal.pone.0107171
View
... The analysis of muscle fiber composition in 40 young men revealed higher percentage of slow-twitch fibers in 7G homozygotes compared to 7C homozygotes [15], although a statistical significance could not be reached due to a low frequency of 7C/7C genotypes (n = 4). In another study PPARA intron 7 G/C variant along with ACE I/D variant were found to be the strongest predictors for muscle fiber type determination [16]. Group of Ahmetov et al. [17] included 7G allele of PPARA gene among ten ''endurance alleles'' whose number positively correlated with the proportion of slow-twitch muscle fibers, and with maximal oxygen consumption. ...
... Under the circumstances it is possible that during intense exercise 7C carriers are more prone to rely on anaerobic processes what may be an adaptive stimulus leading to muscle fiber transformation. A muscle fiber composition have not been monitored in our study, but at least two studies associated PPARA 7 G/C genotypes with a muscle fiber specific composition in athletes [15,16]. Whilst initial composition is likely to be strongly influenced by genetic factors, training has significant effects on fiber shifts and related muscle metabolism changes. ...
PPARA Intron Polymorphism Associated with Power Performance in 30-s Anaerobic Wingate Test
Article
Full-text available
To date, polymorphisms in several genes have been associated with a strength/power performance including alpha 3 actinin, ciliary neurotrophic factor, vitamin D receptor, or angiotensin I converting enzyme, underlining the importance of genetic component of the multifactorial strength/power-related phenotypes. The single nucleotide variation in peroxisome proliferator-activated receptor alpha gene (PPARA) intron 7 G/C (rs4253778; g.46630634G>C) has been repeatedly found to play a significant role in response to different types of physical activity. We investigated the effect of PPARA intron 7 G/C polymorphism specifically on anaerobic power output in a group of 77 elite male Czech ice hockey players (18-36 y). We determined the relative peak power per body weight (Pmax.kg-1) and relative peak power per fat free mass (W.kg-1FFM) during the 30-second Wingate Test (WT30) on bicycle ergometer (Monark 894E Peak bike, MONARK, Sweden). All WT30s were performed during the hockey season. Overall genotype frequencies were 50.6% GG homozygotes, 40.3% CG heterozygotes, and 9.1% CC homozygotes. We found statistically significant differences in Pmax.kg-1 and marginally significant differences in Pmax.kg-1FFM values in WT30 between carriers and non-carriers for C allele (14.6±0.2 vs. 13.9±0.3 W.kg-1 and 15.8±0.2 vs. 15.2±0.3 W.kg-1FFM, P = 0.036 and 0.12, respectively). Furthermore, Pmax.kg-1FFM strongly positively correlated with the body weight only in individuals with GG genotypes (R = 0.55; p<0.001). Our results indicate that PPARA 7C carriers exhibited higher speed strength measures in WT30. We hypothesize that C allele carriers within the cohort of trained individuals may possess a metabolic advantage towards anaerobic metabolism.
View
... There is recent evidence that ACE genotype influences the muscle volume of healthy older men and women (Charbonneau et al. 2008), a key determinant of muscle strength and power. The possibility that the DD genotype may be associated with a greater proportion of fast twitch fibres (Zhang et al. 2003) could explain any influence of the ACE D allele upon strength/ power, particularly at high velocities, but this evidence remains equivocal (Akhmetov et al. 2006). Several investigations have found no association of ACE genotype with isometric and dynamic strength in young and older adults (Folland et al. 2000;Mc Cauley et al. 2009;Pescatello et al. 2006;Woods et al. 2001b). ...
... We found no evidence that ACE genotype is associated with muscle phenotypes of dynamic strength and power or contractile properties in 60-70-year-old men. There are conflicting reports of the influence of ACE genotype on skeletal muscle fibre-type composition (Zhang et al. 2003;Akhmetov et al. 2006). Both relative torque at high velocity, the 240:30°s -1 ratio, and the time course of the twitch response are thought to reflect fibre-type composition (Gür et al. 2003; Edwards Data are mean ± SD WB lean mass whole body non-skeletal lean mass, thigh lean mass non-skeletal lean mass of the non-dominant thigh, TPT time-to-peak tension, HRT half-relaxation time, peak RFD peak rate of force development et al. 1977), but the similarity of our results for these functional indicators suggests no strong ACE genotype effect on the fibre-type composition of older Caucasian men. ...
ACE I/D and ACTN3 R/X polymorphisms and muscle function and muscularity of older Caucasian men
Article
The progressive decline in strength and power with ageing leads to compromised mobility and an increased risk of falls. Angiotensin converting enzyme (ACE) I/D and alpha actinin 3 (ACTN3) R/X polymorphisms have been suggested to influence variations in skeletal muscle function and body composition. This study investigated the associations between these polymorphisms and knee extensor muscle function and muscularity in older Caucasian men. Strength was measured isometrically and isokinetically (at 30 and 240 degrees s(-1)), and the time course of the evoked twitch response recorded. A dual-energy X-ray absorptiometry scan measured thigh and whole body non-skeletal lean mass. ACE I/D and ACTN3 R/X polymorphisms were determined by polymerase chain reaction, and serum ACE activity using spectrophotometry. Whole body and thigh non-skeletal lean mass were independent of ACE and ACTN3 genotypes. Absolute and relative high velocity strength, and the time course of an evoked twitch were not associated with ACE or ACTN3 genotype. Serum ACE activity was negatively correlated with relative high velocity torque (R = -0.23, P = 0.03), and exhibited a positive trend with knee extensor isometric strength (R = 0.19, P = 0.07). ACE I/D and ACTN3 R/X polymorphisms were not associated with muscle function or muscularity phenotypes in older Caucasian men, although serum ACE activity appeared to have a small effect on muscle function.
View
... These heritable factors may include DNA sequence variants, such as single nucleotide polymorphisms (SNPs), indels, and structural variations, which can alter gene expression and/or protein structure but, to date, relatively few candidates have been identified that specifically associate with fibre type. Genetic variants that are known to associate with differences in muscle fibre type, include angiotensinconverting enzyme (ACE) [16][17][18], alpha-actinin 3 (ACTN3) [18][19][20], type 2 angiotensin receptor (AGTR2) [21], brain derived neurotrophic factor (BDNF) [22], cerebellin 2 precursor (CBLN2) [23], copine 5 (CPNE5) [24], fat mass and obesity-associated (FTO) [25], hypoxiainduced factor 1-alpha (HIF1A) [26], immunoglobulin superfamily member 3 (IGSF3) [27], mitochondrial ORF of the 12S rRNA type-c (MOTS-c) encoded within the mitochondrial 12S rRNA [28], nuclear respiratory factor 1 (NRF1) [29], peroxisome-induced alpha receptor (PPARA) [30], peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) [29], striated muscle enriched protein kinase (SPEG) [31], transforming growth factor alpha (TGFA) [32], vascular endothelium growth factor receptor 2 (VEGFR2) [33] genes, with additional variants likely to exist. In addition, individual genetic variants may combine to influence the composition of muscle fibers through different pathways [34,35]. ...
Genome-Wide Association Study Identifies CDKN1A as a Novel Locus Associated with Muscle Fiber Composition
Article
Full-text available
  • Dec 2022
Muscle fiber composition is associated with physical performance, with endurance athletes having a high proportion of slow-twitch muscle fibers compared to power athletes. Approximately 45% of muscle fiber composition is heritable, however, single nucleotide polymorphisms (SNP) underlying inter-individual differences in muscle fiber types remain largely unknown. Based on three whole genome SNP datasets, we have shown that the rs236448 A allele located near the cyclin-dependent kinase inhibitor 1A (CDKN1A) gene was associated with an increased proportion of slow-twitch muscle fibers in Russian (n = 151; p = 0.039), Finnish (n = 287; p = 0.03), and Japanese (n = 207; p = 0.008) cohorts (meta-analysis: p = 7.9 × 10−5. Furthermore, the frequency of the rs236448 A allele was significantly higher in Russian (p = 0.045) and Japanese (p = 0.038) elite endurance athletes compared to ethnically matched power athletes. On the contrary, the C allele was associated with a greater proportion of fast-twitch muscle fibers and a predisposition to power sports. CDKN1A participates in cell cycle regulation and is suppressed by the miR-208b, which has a prominent role in the activation of the slow myofiber gene program. Bioinformatic analysis revealed that the rs236448 C allele was associated with increased CDKN1A expression in whole blood (p = 8.5 × 10−15) and with greater appendicular lean mass (p = 1.2 × 10−5), whereas the A allele was associated with longer durations of exercise (p = 0.044) reported amongst the UK Biobank cohort. Furthermore, the expression of CDKN1A increased in response to strength (p < 0.0001) or sprint (p = 0.00035) training. Accordingly, we found that CDKN1A expression is significantly (p = 0.002) higher in the m. vastus lateralis of strength athletes compared to endurance athletes and is positively correlated with the percentage of fast-twitch muscle fibers (p = 0.018). In conclusion, our data suggest that the CDKN1A rs236448 SNP may be implicated in the determination of muscle fiber composition and may affect athletic performance.
View
... To date, few studies have sought to define the impact of gene polymorphisms on human muscle fibre composition. There have been reports that five polymorphisms of angiotensin-converting enzyme (ACE), alpha-actinin-3 (ACTN3), hypoxia inducible factor 1 alpha (HIF1A), peroxisome proliferator-activated receptor alpha (PPARA) and vascular endothelial growth factor receptor 2 (VEGFR2) genes (involved in the calcineurin/NFAT pathway, glucose and lipid metabolism, cytoskeletal function, hypoxia/angiogenesis and circulatory homeostasis) are associated with muscle fibre composition ( Zhang et al. 2003;Ahmetov et al. 2006Ahmetov et al. , 2008Ahmetov et al. , 2009aAhmetov et al. ,b, 2011Akhmetov et al. 2006;Vincent et al. L. J. Mustafina and others 2007). ...
AGTR2 gene polymorphism is associated with muscle fibre composition, athlete status and aerobic performance
Article
Full-text available
  • May 2014
What is the central question of this study? Variations in genes are considered to be molecular determinants maintaining the expression of the slow or fast myosin heavy chains of adult skeletal muscle. The role of polymorphisms of candidate genes involved in skeletal muscle development, energy homeostasis and thyroid and calcium metabolism in the determination of muscle fibre type has not previously been reported.What is the main finding and its importance? We show that the AGTR2 rs11091046 C allele is associated with an increased proportion of slow-twitch muscle fibres, endurance athlete status and aerobic performance. Such findings have important implications for our understanding of muscle function in both health and disease.
View
... PPARα is a ligand-activated transcription factor that regulates the expression of genes involved in fatty acid uptake and oxidation, glucose and lipid metabolism, left ventricular growth and control of Jamshidi et al. (2002) have shown that British army recruits homozygous for the rare PPARA gene C allele of the rs4253778 (intron 7 G/ C) polymorphism had a 3-fold greater increase in LV mass in response to training than G allele homozygotes. The hypothesis that intron 7 C allele is associated with the hypertrophic effect due to influences on cardiac and skeletal muscle substrate utilisation was supported by the findings that PPARA C allele is over-represented in Russian power-oriented athletes (Ahmetov et al., 2006) and associated with an increased proportion of fast-twitch muscle fibres in m. vastus lateralis of physically active men (Akhmetov et al., 2006). In our study, we found that elite football players, and in particular attackers, had higher frequencies of the PPARA C allele than controls. ...
The polygenic profile of Russian football players
Article
Full-text available
Abstract Research concerned with predictors of talent in football has highlighted a number of potentially important and partially inherited measures such as body size, anaerobic power, aerobic capacity, agility, psychological profile, game intelligence and susceptibility to injuries. Genotyping for performance-associated DNA polymorphisms at an early age could be useful in predicting later success in football. The aim of the study was to investigate individually and in combination the association of common gene polymorphisms with football player's status. A total of 246 Russian football players and 872 controls were genotyped for 8 gene polymorphisms, which were previously reported to be associated with athlete status. Four alleles (ACE D, ACTN3 Arg577, PPARA rs4253778 C and UCP2 55Val) were first identified, showing discrete associations with football player's status. Next, we determined the total genotype score (TGS, from the accumulated combination of the 4 polymorphisms, with a maximum value of 100 for the theoretically optimal polygenic score) in athletes and controls. The mean TGS was significantly higher in football players (52.0 (17.6) vs. 41.3 (15.5); P < 0.0001) than in controls. These data suggest that the likelihood of becoming a football player depends on the carriage of a high number of "favourable" gene variants.
View
... European Journal of Sport Science 2011, 1Á7, iFirst article endurance athletes and controls (Jones, Montgomery, & Woods, 2002; Myerson et al., 1999; Nazarov et al., 2001; Woods, D. et al., 2001). This genotype has been associated with a greater proportion of fast twitch fibres (Zhang et al., 2003), suggesting that this polymorphism may influence skeletal muscle function , although contradictory evidence also exists (Akhmetov et al., 2006 ). However, studies investigating the association between ACE I/D genotype and skeletal muscle strength phenotypes have yielded inconsistent results. ...
Lack of association of the ACE genotype with the muscle strength response to resistance training
Article
Full-text available
Introduction: Previous studies have attempted to link the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene with the variability in muscle strength responses to resistance training (RT); however, the literature is inconclusive. The purpose of the present study was to investigate the association between the ACE I/D genotype and muscle strength response to a RT program in young men.Methods: 124 men (22±2.6 years; 174.8±6.5cm; 71.5±13.8 kg) without resistance training experience were tested before and after 11 weeks of five whole-body RT exercises (bench press, seated row, knee extension, knee flexion and sit ups). The bench press 1RM test was used to assess upper-body muscle strength and the isokinetic knee extensor peak torque (PT) was used as a measure of lower-body strength.Results: At baseline, there were no differences among ACE genotype for 1RM load (54±11.7 kg for II, 58.5±8.9 kg for ID and 52.3±12.2 kg for DD) or knee extensor peak torque (PT) (220.1±36.8 N·m for II, 209.4 ±44.4 N·m for ID and 199.7±32.4 N·m for DD). Moreover, ACE genotype was not associated with lower-body (7.1±10.5%, 15.7±10.4% and 14.1±22.7% for II, ID and DD, respectively) or upper-body strength gains (16.2±8.9%, 14.5±11.3% and 21.9±17.1% for II, ID and DD, respectively) in response to RT.Conclusion: The ACE I/D genotype was not associated with the muscle strength responses to RT.
View
Associação dos polimorfismo da alfa-actinina 3 (ACTN3) e enzima conversora da angiotensina (ECA) com indicadores do desempenho em atletas
Thesis
Full-text available
  • Mar 2014
The aim of this study was to identify the association between ACTN3 (R577X) and ACE (I/D) gene polymorphisms and athletic performance type (endurance, speed/power and mixed). The sample consisted of 176 athletes (100 men and 76 women) with mean age of 16.75 years ± 3.50. We studied 22 sports; all athletes were chosen from the best in their respective Federations of the State of Paraná. DNA samples were withdrawn from 4ml of blood from the median cubital vein. Genotyping of the ACTN3 - R577X gene polymorphism were performed using a TaqMan probe ID rs1815739 (Applied Biosystems, Foster City, CA, USA ). Genotyping of the ACE I / D polymorphism were performed by polymerase chain reaction (PCR), followed by visualization by electrophoresis. The physical tests were vertical jumps (Squat Jump, Jump and Countermovement Jump with help of the arms), speed in the 30m sprint (in seconds) and maximum oxygen consumption (VO2max). Statistical analysis was done with the chi-square test and One Way ANOVA , with significance at p < 0.05. Genotypes were not statistically significant with the duration of effort (ACTN3 vs Duration of Effort, p = 0.709 ; ACE VS Length of Effort, p = 0.140). The prevalence of RX and DI genes were more prevalent in the duration of effort (resistance : RX = 60.6 % , DI = 4.87 %, Power / Speed : . RX = 54.1 % , DI = 50 % ; Mixed: RX = 45 % , DI = 41.98 % ). We therefore conclude that genetic variables show a prevalence that can help in determining the choice of a sport / event that requires a specific type of metabolism to exercise in young athletes, although there was no association between polymorphisms ACTN3 and ACE in relation to exercise duration and physical performance. Key Words: polymorphisms, genotypes, physical performance.
View
Heterogeneity of quadriceps muscle phenotype in chronic obstructive pulmonary disease (COPD); implications for stratified medicine?
Article
Full-text available
Introduction: Quadriceps muscle dysfunction is common in COPD. Determining, and, if possible, predicting quadriceps phenotype in COPD is important for patient stratification for therapeutic trials. Methods: In biopsies from 114 COPD patients and 30 controls, we measured fiber size and proportion and assessed the relationship with quadriceps function (strength and endurance), clinical phenotype (lung function, physical activity, fat-free mass) and exercise performance. In a subset (n = 40) we measured muscle mid-thigh cross-sectional area by computed tomography. Results: Normal ranges for fiber proportions and fiber cross-sectional area were defined from controls; we found isolated fiber shift in 31% of patients, isolated fiber (predominantly type II) atrophy in 20%, both shift and atrophy in 25%, and normal fiber parameters in 24%. Clinical parameters related poorly to muscle biopsy appearances. Conclusions: Quadriceps morphology is heterogeneous in COPD and cannot be predicted without biopsy, underlining the need for biomarkers.
View
Gene Polymorphisms and Fiber-Type Composition of Human Skeletal Muscle
Article
Full-text available
The ability to perform aerobic or anaerobic exercise varies widely among individuals, partially depending on their muscle-fiber composition. Variability in the proportion of skeletal-muscle fiber types may also explain marked differences in aspects of certain chronic disease states including obesity, insulin resistance, and hypertension. In untrained individuals, the proportion of slow-twitch (Type I) fibers in the vastus lateralis muscle is typically around 50% (range 5-90%), and it is unusual for them to undergo conversion to fast-twitch fibers. It has been suggested that the genetic component for the observed variability in the proportion of Type I fibers in human muscles is on the order of 40-50%, indicating that muscle fiber-type composition is determined by both genotype and environment. This article briefly reviews current progress in the understanding of genetic determinism of fiber-type proportion in human skeletal muscle. Several polymorphisms of genes involved in the calcineurin-NFAT pathway, mitochondrial biogenesis, glucose and lipid metabolism, cytoskeletal function, hypoxia and angiogenesis, and circulatory homeostasis have been associated with fiber-type composition. As muscle is a major contributor to metabolism and physical strength and can readily adapt, it is not surprising that many of these gene variants have been associated with physical performance and athlete status, as well as metabolic and cardiovascular diseases. Genetic variants associated with fiber-type proportions have important implications for our understanding of muscle function in both health and disease.
View
View
The angiotensin converting enzyme I/D polymorphism in Russian athletes
Article
Full-text available
  • Oct 2001
The deletion (D) allele of the human ACE gene is associated with higher ACE activity than the insertion (I) allele. There is controversy as to whether the ACE genotype may be associated with elite athletic status; recent studies have identified no significant associations amongst those drawn from mixed sporting disciplines. However, such lack of association may reflect the mixed nature of such cohorts, given that an excess frequency of the I allele has been reported amongst elite endurance athletes, and an excess of the D allele amongst those engaged in more power-orientated sports. We examined this hypothesis by determining ACE I/D allele frequency amongst 217 Russian athletes (swimmers, skiers, triathletes and track-and-field participants) prospectively stratified by performance ('outstanding' or 'average'), and the duration of their event (SDA (<1 min), MDA (1 to 20 min), and LDA (>20 min): short, middle and long distance athletes respectively). ACE genotype and allele frequencies were compared to 449 controls. ACE genotype frequency amongst the whole cohort, or the outstanding athletes alone, was no different to that amongst sedentary controls. However, there was an excess of the D allele (frequency 0.72, P=0.001) amongst the outstanding SDA group, and an excess of the I allele (frequency 0.63, P=0.032) amongst the outstanding MDA group. These findings were replicated in the outstanding swimmers, with track and field SDA similarly demonstrating an excess of the D allele (P=0.01). There was no association found between the outstanding LDA and ACE genotype (P=0.27). These data not only confirm an excess of the D allele in elite SDA, and I allele in elite MDA, but also offer an explanation as to why any such association may be hard to detect amongst a heterogeneous cohort of mixed athletic ability and discipline.
View
Peroxisome proliferator--activated receptor alpha gene regulates left ventricular growth in response to exercise and hypertension
Article
Full-text available
Left ventricular hypertrophy (LVH) occurs as an adaptive response to a physiological (such as exercise) or pathological (valvular disease, hypertension, or obesity) increase in cardiac work. The molecular mechanisms regulating the LVH response are poorly understood. However, inherited defects in fatty acid oxidation are known to cause severe early-onset cardiac hypertrophy. Peroxisome proliferator--activated receptor alpha (PPARalpha) regulates genes responsible for myocardial fatty acid oxidation and is downregulated during cardiac hypertrophy, concomitant with the switch from fatty acid to glucose utilization. The role of PPARalpha in left ventricular growth was investigated in 144 young male British Army recruits undergoing a 10-week physical training program and in 1148 men and women participating in the echocardiographic substudy of the Third Monitoring Trends and Determinants in Cardiovascular Disease (MONICA) Augsburg study. A G/C polymorphism in intron 7 of the PPARalpha gene significantly influenced left ventricular (LV) growth in response to exercise (P=0.009). LV mass increased by 6.7 +/- 1.5 g in G allele homozygotes but was significantly greater in heterozygotes for the C allele (11.8 +/- 1.9 g) and in CC homozygotes (19.4 +/- 4.2 g). Likewise, C allele homozygotes had significantly higher LV mass, which was greater still in hypertensive subjects, and a higher prevalence of LVH in the Third MONICA Augsburg study. We demonstrate that variation in the PPARalpha gene influences human left ventricular growth in response to exercise and hypertension, indicating that maladaptive cardiac substrate utilization can play a causative role in the pathogenesis of LVH.
View
ACTN3 Genotype Is Associated with Human Athletic Performance
Article
Full-text available
  • Oct 2003
There is increasing evidence for strong genetic influences on athletic performance and for an evolutionary "trade-off" between performance traits for speed and endurance activities. We have recently demonstrated that the skeletal-muscle actin-binding protein alpha-actinin-3 is absent in 18% of healthy white individuals because of homozygosity for a common stop-codon polymorphism in the ACTN3 gene, R577X. alpha-Actinin-3 is specifically expressed in fast-twitch myofibers responsible for generating force at high velocity. The absence of a disease phenotype secondary to alpha-actinin-3 deficiency is likely due to compensation by the homologous protein, alpha-actinin-2. However, the high degree of evolutionary conservation of ACTN3 suggests function(s) independent of ACTN2. Here, we demonstrate highly significant associations between ACTN3 genotype and athletic performance. Both male and female elite sprint athletes have significantly higher frequencies of the 577R allele than do controls. This suggests that the presence of alpha-actinin-3 has a beneficial effect on the function of skeletal muscle in generating forceful contractions at high velocity, and provides an evolutionary advantage because of increased sprint performance. There is also a genotype effect in female sprint and endurance athletes, with higher than expected numbers of 577RX heterozygotes among sprint athletes and lower than expected numbers among endurance athletes. The lack of a similar effect in males suggests that the ACTN3 genotype affects athletic performance differently in males and females. The differential effects in sprint and endurance athletes suggests that the R577X polymorphism may have been maintained in the human population by balancing natural selection.
View
High-Throughput Method for Determination of Apolipoprotein E Genotypes with Use of Restriction Digestion Analysis by Microplate Array Diagonal Gel Electrophoresis
Article
  • Dec 1995
Molecular epidemiological research has identified the association of a common apolipoprotein E (apo E) isoform (E4 as opposed to E3), with risk both of coronary artery disease and of Alzheimer dementia. In addition, the role of apo E genotype (usually E2/E2) in Type III hyperlipidemia is well known. However, both for diagnostic and research purposes, apo E genotyping is cumbersome. The preferred approach is electrophoretic sizing of restriction digestion fragments, enabling simultaneous analysis of the two codons (112 and 158) that represent the six common genotypes (E2/E2; E2/E3; E2/E4; E3/E3; E3/E4; E4/E4). However, the consequent demands of high-yield PCR, high-resolution, high-throughput electrophoresis, and sufficient detection sensitivity have left shortfalls in published protocols. In conjunction with a high-throughput electrophoresis system we described recently, microplate array diagonal gel electrophoresis (MADGE), we have constructed extensively optimized, simplified protocols for DNA isolation from mouthwash samples for PCR setup and high-yield PCR, for restriction digestion, and for subsequent MADGE gel image analysis. The integral system enables one worker to readily undertake apo E genotyping of as many as hundreds of DNA samples per day, without special equipment.
View
Differential expression for the actin-binding proteins, α-actinin-2 and -3, in different species: Implications for the evolution of functional redundancy
Article
  • Jul 2001
The α-actinins are a multigene family of four actin-binding proteins related to dystrophin. The two skeletal muscle isoforms of α-actinin (ACTN2 and ACTN3) are major structural components of the Z-line involved in anchoring the actin-containing thin filaments. In humans, ACTN2 is expressed in all muscle fibres, while ACTN3 expression is restricted to a subset of type 2 fibres. We have recently demonstrated that α-actinin-3 is absent in ∼ 18% of individuals in a range of human populations, and that homozygosity for a premature stop codon (577X) accounts for most cases of true α-actinin-3 deficiency. Absence of α-actinin-3 is not associated with an obvious disease phenotype, raising the possibility that ACTN3 is functionally redundant in humans, and that α-actinin-2 is able to compensate for α-actinin-3 deficiency. We now present data concerning the expression of ACTN3 in other species. Genotyping of non-human primates indicates that the 577X null mutation has likely arisen in humans. The mouse genome contains four orthologues which all map to evolutionarily conserved syntenic regions for the four human genes. Murine Actn2 and Actn3 are differentially expressed, spatially and temporally, during embryonic development and, in contrast to humans, α-actinin-2 expression does not completely overlap α-actinin-3 in postnatal skeletal muscle, suggesting independent function. Furthermore, sequence comparison of human, mouse and chicken α-actinin genes demonstrates that ACTN3 has been conserved over a long period of evolutionary time, implying a constraint on evolutionary rate imposed by continued function of the gene. These observations provide a real framework in which to test theoretical models of genetic redundancy as they apply to human populations. In addition we highlight the need for caution in making conclusions about gene function from the phenotypic consequences of loss-of-function mutations in animal knockout models.
View
Peroxisome Proliferator-Activated Receptor Gene Variants Influence Progression of Coronary Atherosclerosis and Risk of Coronary Artery Disease
Article
Peroxisome proliferator-activated receptor alpha (PPARalpha) regulates the expression of genes involved in lipid metabolism and inflammation, making it a candidate gene for atherosclerosis and ischemic heart disease (IHD). We investigated the association between the leucine 162 to valine (L162V) polymorphism and a G to C transversion in intron 7 of the PPARalpha gene and progression of atherosclerosis in the Lopid Coronary Angiography Trial (LOCAT), a trial examining the effect of gemfibrozil treatment on progression of atherosclerosis after bypass surgery and on risk of IHD in the second Northwick Park Heart Study (NPHS2), a prospective study of healthy middle-aged men in the United Kingdom. There was no association with plasma lipid concentrations in either study. Both polymorphisms influenced progression of atherosclerosis and risk of IHD. V162 allele carriers had less progression of diffuse atherosclerosis than did L162 allele homozygotes with a similar trend for focal atherosclerosis. Intron 7 C allele carriers had greater progression of atherosclerosis than did G allele homozygotes. The V162 allele attenuated the proatherosclerotic effect of the intron 7 C allele. Homozygotes for the intron 7 C allele had increased risk of IHD, an effect modulated by the L162V polymorphism The PPARalpha gene affects progression of atherosclerosis and risk of IHD. Absence of association with plasma lipid concentrations suggests that PPARalpha affects atherosclerotic progression directly in the vessel wall.
View
A method of determination of hundreds of APOE genotypes utilizing highly simplified, optimized protocols and restriction digestion analysis by microtitre array diagonal gel electrophoresis (MADGE)
  • Jan 1995
  • 1599-1604
  • M K Bolla
  • L Haddad
  • S E Humphries
  • A F Winder
  • I N M Day
Bolla M.K., Haddad L., Humphries S.E., Winder A.F., Day I.N.M. A method of determination of hundreds of APOE genotypes utilizing highly simplified, optimized protocols and restriction digestion analysis by microtitre array diagonal gel electrophoresis (MADGE). Clin Chem. 41: 1599-1604. 1995.
Differential expression of the actin-binding proteins, alpha-actinin-2 and -3, in different species: implications for the evolution of functional redundancy The angiotensin converting enzyme I/D polymorphism in Russian athletes
  • Jan 2001
  • 1335-46
  • M Mills
  • N Yang
  • R Weinberger
  • D L Vander
  • A H Beggs
  • S Easteal
  • Kb North
  • D R Woods
  • H E Montgomery
  • O V Shneider
  • V I Kazakov
  • N V Tomilin
  • V A Rogozkin
Mills M., Yang N., Weinberger R., Vander Woude D.L., Beggs A.H., Easteal S., North K. Differential expression of the actin-binding proteins, alpha-actinin-2 and -3, in different species: implications for the evolution of functional redundancy. Hum Mol Genet.10 (13): 1335-46. 2001. 888 6. Nazarov I.B., Woods D.R., Montgomery H.E., Shneider O.V., Kazakov V.I., Tomilin N.V., Rogozkin V.A. The angiotensin converting enzyme I/D polymorphism in Russian athletes. Eur J Hum Genet. 9 (10): 797-801. 2001.