Dallas M Swallow

The University of Manchester, Manchester, ENG, United Kingdom

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Publications (26)157.88 Total impact

  • Article: MUC5AC & inflammatory mediators associated with respiratory outcomes in the British 1946 birth cohort.
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    ABSTRACT: BACKGROUNDAND OBJECTIVE: Dysregulation of respiratory mucins, MUC5AC in particular, has been implicated in respiratory disease and MUC5AC expression is up-regulated in response to environmental challenges and inflammatory mediators. Our aim is to examine the effect of genetic variation on susceptibility to common respiratory conditions. METHODS: We test for association of MUC5AC and the closely linked genes MUC2 and MUC5B with respiratory outcomes in the MRC National Survey of Health and Development (NSHD), a longitudinal birth cohort of men and women born in 1946. We also examine functional variants of the genes encoding inflammatory mediators,IL13, IL1B, IL1RN, TNFA and ERBB1 for which there is a likely influence on MUC5AC expression, and explore potential gene-gene interactions with these inflammatory mediators with respect to respiratory disease. RESULTS: We report here statistically significant associations between the 3'ter MUC5AC SNP rs1132440 and various non-independent respiratory outcomes (bronchitis, wheeze, asthma, hay fever) while the adjacent loci show slight (but largely non-statistically significant) differences, presumably reflective of linkage disequilibrium (allelic association) across the region. A novel association between bronchitis and a non-synonymous functional ERBB1 SNP, rs2227983 (aka EGFR:R497K, R521K) is also reported and evidence presented of interaction between MUC5AC and ERBB1 and between MUC5AC and IL1RN with respect to bronchitis. The ERBB1 interaction suggests a clear mechanism for a biological interaction in which the allelic variants of EGFR differentially affect mucin expression. CONCLUSIONS: The MUC5AC association and the interactions with inflammatory mediatorssuggest that genetically determined differences in MUC5AC expression alter susceptibility to respiratory disease.
    Respirology 04/2013; · 2.42 Impact Factor
  • Article: Mucin methods: genes encoding mucins and their genetic variation with a focus on gel-forming mucins.
    Karine Rousseau, Dallas M Swallow
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    ABSTRACT: Mucin genes encode the polypeptide backbone of the mucin glycoproteins which are expressed on all epithelial surfaces and are major constituents of the mucus layer. Mucins are, thus, expressed at the interface between the external and the internal environment of the organism, and represent the first line of defence of our body. These genes often have an extensive region of repetitive exonic sequence which codes for the heavily glycosylated domain, whose roles include bacterial interactions and gel hydration. This region shows, in several of the genes, considerable inter-individual variation in repeat number and sequence. Because of their site of expression and their high variability in this important domain, mucin genes are good candidates for conferring differences in genetic susceptibility to multifactorial epithelial and inflammatory disease. However, progress in characterizing the genes has been considerably slower than the rest of the genome because of their size and the GC-rich content of the large, repetitive variable region. Some of the issues relating to the study of these genes are discussed in this chapter. In addition, methods and approaches that have been used successfully are described.
    Methods in molecular biology (Clifton, N.J.) 01/2012; 842:1-26.
  • Article: The impact of cis-acting polymorphisms on the human phenotype.
    Bryony L Jones, Dallas M Swallow
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    ABSTRACT: Cis-acting polymorphisms that affect gene expression are now known to be frequent, although the extent and mechanisms by which such variation affects the human phenotype are, as yet, only poorly understood. Key signatures of cis-acting variation are differences in gene expression that are tightly associated with regulatory SNPs or expression Quantitative Trait Loci (eQTL) and an imbalance of allelic expression (AEI) in heterozygous samples. Such cis-acting sequence differences appear often to have been under selection within and between populations and are also thought to be important in speciation. Here we describe the example of lactase persistence. In medical research, variants that affect regulation in cis have been implicated in both monogenic and polygenic disorders, and in the metabolism of drugs. In this review we suggest that by further understanding common regulatory variations and how they interact with other genetic and environmental variables it will be possible to gain insight into important mechanisms behind complex disease, with the potential to lead to new methods of diagnosis and treatments.
    The HUGO journal. 12/2011; 5(1-4):13-23.
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    Article: Herders of Indian and European cattle share their predominant allele for lactase persistence.
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    ABSTRACT: Milk consumption and lactose digestion after weaning are exclusively human traits made possible by the continued production of the enzyme lactase in adulthood. Multiple independent mutations in a 100-bp region--part of an enhancer--approximately 14-kb upstream of the LCT gene are associated with this trait in Europeans and pastoralists from Saudi Arabia and Africa. However, a single mutation of purported western Eurasian origin accounts for much of observed lactase persistence outside Africa. Given the high levels of present-day milk consumption in India, together with archaeological and genetic evidence for the independent domestication of cattle in the Indus valley roughly 7,000 years ago, we sought to determine whether lactase persistence has evolved independently in the subcontinent. Here, we present the results of the first comprehensive survey of the LCT enhancer region in south Asia. Having genotyped 2,284 DNA samples from across the Indian subcontinent, we find that the previously described west Eurasian -13910 C>T mutation accounts for nearly all the genetic variation we observed in the 400- to 700-bp LCT regulatory region that we sequenced. Geography is a significant predictor of -13910*T allele frequency, and consistent with other genomic loci, its distribution in India follows a general northwest to southeast declining pattern, although frequencies among certain neighboring populations vary substantially. We confirm that the mutation is identical by descent to the European allele and is associated with the same>1 Mb extended haplotype in both populations.
    Molecular Biology and Evolution 08/2011; 29(1):249-60. · 5.55 Impact Factor
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    Article: Prevalence of clinically relevant UGT1A alleles and haplotypes in African populations.
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    ABSTRACT: Variation of a short (TA)(n) repeat sequence (rs8175347) covering the TATA box of UGT1A1 (UDP-glucuronosyltransferase1A1) is associated with hyperbilirubinaemia (Gilbert's syndrome) and adverse drug reactions, and is used for dosage advice for irinotecan. Several reports indicate that the low-activity (risk) alleles ((TA)(7) and (TA)(8) )) are very frequent in Africans but the patterns of association with other variants in the UGT1A gene complex that may modulate these responses are not well known. rs8175347 and two other clinically relevant UGT1A variants (rs11692021 and rs10929302) were assayed in 2616 people from Europe and Africa. Low-activity (TA)(n) alleles frequencies were highest in equatorial Africa, (TA)(7,) being the most common in Cameroon, Ghana, southern Sudan, and in Ethiopian Anuak. Haplotypic diversity was also greatest in equatorial Africa, but in Ethiopia was very variable across ethnic groups. Resequencing of the promoter of a sample subset revealed no novel variations, but rs34547608 and rs887829 were typed and shown to be tightly associated with (TA)(n) . Our results illustrate the need for investigation of the effect of UGT1A variants other than (TA)(n) on the risk of irinotecan toxicity, as well as hyperbilirubinaemia due to hemolytic anaemia or human immunodeficiency virus protease inhibitors, so that appropriate pharmacogenetic advice can be given.
    Annals of Human Genetics 03/2011; 75(2):236-46. · 2.57 Impact Factor
  • Article: Evolution of lactase persistence: an example of human niche construction.
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    ABSTRACT: Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (-13910*T) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle East. Current estimates for the age of lactase persistence-associated alleles bracket those for the origins of animal domestication and the culturally transmitted practice of dairying. We report new data on the distribution of -13910*T and summarize genetic studies on the diversity of lactase persistence worldwide. We review relevant archaeological data and describe three simulation studies that have shed light on the evolution of this trait in Europe. These studies illustrate how genetic and archaeological information can be integrated to bring new insights to the origins and spread of lactase persistence. Finally, we discuss possible improvements to these models.
    Philosophical Transactions of The Royal Society B Biological Sciences 03/2011; 366(1566):863-77. · 6.40 Impact Factor
  • Article: Serum bilirubin and risk of respiratory disease and death.
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    ABSTRACT: Serum total bilirubin levels in healthy patients reflect genetic and environmental factors that could influence the risk of developing respiratory disease. To examine the relationship between bilirubin levels and respiratory disease. Cohort study among 504,206 adults from a UK primary care research database (the Health Improvement Network) with serum bilirubin levels recorded but no evidence of hepatobiliary or hemolytic disease. Data were recorded between January 1988 and December 2008. Incidence of chronic obstructive pulmonary disease (COPD), lung cancer, and all-cause mortality. Median bilirubin levels were 0.64 mg/dL (interquartile range, 0.47-0.88 mg/dL) in men and 0.53 mg/dL (interquartile range, 0.41-0.70 mg/dL) in women. There were 1341 cases of lung cancer, 5863 cases of COPD, and 23,103 deaths, with incidence rates of 2.5, 11.9, and 42.5 per 10,000 person-years, respectively. The incidence of lung cancer per 10,000 person-years in men was 5.0 (95% confidence interval [CI], 4.2-6.0) in the first decile category of bilirubin compared with 3.0 (95% CI, 2.3-3.8) in the fifth decile. The corresponding incidences for COPD in men were 19.5 (95% CI,17.7-21.4) and 14.4 (95% CI, 12.7-16.2). The mortality rates per 10,000 person-years in men were 51.3 (95% CI, 48.5-54.2) in the first decile category compared with 38.1 (95% CI, 35.5-40.8) in the fifth decile. The associations were similar for women. After adjusting for other important health indicators, regression estimates for incidence rate of lung cancer per 0.1-mg/dL increase in bilirubin level were an 8% decrease (95% CI, 5%-11%) for men and an 11% decrease (95% CI, 7%-14%) for women. The regression estimate for COPD in men per 0.1-mg/dL increase in bilirubin level was a 6% decrease (95% CI, 5%-7%) and for mortality in men was a 3% decrease (95% CI, 2%-3%) after accounting for other health indicators. The results for COPD and mortality in women were very similar. Among patients with normal-range bilirubin levels in primary care practices, relatively higher levels of bilirubin were associated with a lower risk of respiratory disease and all-cause mortality.
    JAMA The Journal of the American Medical Association 02/2011; 305(7):691-7. · 30.03 Impact Factor
  • Article: The -14010*C variant associated with lactase persistence is located between an Oct-1 and HNF1α binding site and increases lactase promoter activity.
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    ABSTRACT: In most people worldwide intestinal lactase expression declines in childhood. In many others, particularly in Europeans, lactase expression persists into adult life. The lactase persistence phenotype is in Europe associated with the -13910*T single nucleotide variant located 13,910 bp upstream the lactase gene in an enhancer region that affects lactase promoter activity. This variant falls in an Oct-1 binding site and shows greater Oct-1 binding than the ancestral variant and increases enhancer activity. Several other variants have been identified very close to the -13910 position, which are associated with lactase persistence in the Middle East and Africa. One of them, the -14010*C, is associated with lactase persistence in Africa. Here we show by deletion analysis that the -14010 position is located in a 144 bp region that reduces the enhancer activity. In transfections the -14010*C allele shows a stronger enhancer effect than the ancestral -4010*G allele. Binding sites for Oct-1 and HNF1α surrounding the -14010 position were identified by gel shift assays, which indicated that -14010*C has greater binding affinity to Oct-1 than -14010*G.
    Human Genetics 02/2011; 130(4):483-93. · 5.07 Impact Factor
  • Article: Cis-acting allelic variation in MUC5B mRNA expression is associated with different promoter haplotypes.
    Andrew X Loh, Lauren Johnson, Wendy Ng, Dallas M Swallow
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    ABSTRACT: Mucins play a critical role in protecting and clearing the airways of noxious materials. Genetic variation that influences this environmental response is likely to affect respiratory disease susceptibility. It has been reported previously that variation in the promoter of MUC5B, the gene that encodes one of the two major gel-forming mucins (MUC5B) of the mucus of the respiratory tract, is associated with susceptibility to diffuse panbronchiolitis, and that a genetic difference in promoter activity can be detected in vitro. The aim of this study was to determine whether this genetic difference in promoter activity can be detected in vivo. Here, we undertake RNA transcript expression studies, making use of human fetal tissue to explore constitutive differences. We compare in vivo transcript expression levels in heterozygotes and use the Bayesian method, PHASE to associate exonic simple nucleotide polymorphisms (SNPs) with promoter SNPs to generate haplotypes. We successfully show haplotypic differences in MUC5B expression in vivo. This genetic variation should be taken into account in future studies on MUC5B in respiratory disease.
    Annals of Human Genetics 11/2010; 74(6):498-505. · 2.57 Impact Factor
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    Article: A worldwide correlation of lactase persistence phenotype and genotypes.
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    ABSTRACT: The ability of adult humans to digest the milk sugar lactose - lactase persistence - is a dominant Mendelian trait that has been a subject of extensive genetic, medical and evolutionary research. Lactase persistence is common in people of European ancestry as well as some African, Middle Eastern and Southern Asian groups, but is rare or absent elsewhere in the world. The recent identification of independent nucleotide changes that are strongly associated with lactase persistence in different populations worldwide has led to the possibility of genetic tests for the trait. However, it is highly unlikely that all lactase persistence-associated variants are known. Using an extensive database of lactase persistence phenotype frequencies, together with information on how those data were collected and data on the frequencies of lactase persistence variants, we present a global summary of the extent to which current genetic knowledge can explain lactase persistence phenotype frequency. We used surface interpolation of Old World lactase persistence genotype and phenotype frequency estimates obtained from all available literature and perform a comparison between predicted and observed trait frequencies in continuous space. By accommodating additional data on sample numbers and known false negative and false positive rates for the various lactase persistence phenotype tests (blood glucose and breath hydrogen), we also apply a Monte Carlo method to estimate the probability that known lactase persistence-associated allele frequencies can explain observed trait frequencies in different regions. Lactase persistence genotype data is currently insufficient to explain lactase persistence phenotype frequency in much of western and southern Africa, southeastern Europe, the Middle East and parts of central and southern Asia. We suggest that further studies of genetic variation in these regions should reveal additional nucleotide variants that are associated with lactase persistence.
    BMC Evolutionary Biology 02/2010; 10:36. · 3.52 Impact Factor
  • Article: Evaluation of a novel reverse-hybridization StripAssay for typing DNA variants useful in diagnosis of adult-type hypolactasia.
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    ABSTRACT: Adult-type hypolactasia is a genetically determined inability to digest lactose after weaning. Two single-nucleotide polymorphisms (C-13910T, G-22018A) located upstream of the lactase gene (LCT) within the gene MCM6 are associated with the lactase persistence/non-persistence trait in patients of European descent. Therefore, the genotyping of these SNPs has been established as a diagnostic tool for adult-type hypolactasia. We have recently shown that several novel allelic variants located in close proximity to the C-13910T SNP interfere with the diagnostic accuracy of real-time PCR-based genotyping methods. We describe here the validation of a comprehensive reverse-hybridization teststrip-based assay for the detection of common and novel LCT SNPs (C-13907G, C-13910T, T-13913C, G-13914A, T-13915G, and G-22018A). This assay is based on multiplex DNA amplification and ready-to-use membrane teststrips containing variant-specific oligonucleotide probes immobilized as an array of parallel lines. We evaluated the novel reverse-hybridization StripAssay on 125 DNA samples in comparison to LightCycler analysis and sequencing. The outcome of StripAssay genotyping was found to be completely concordant with that obtained by sequencing. The StripAssay represents an accurate and robust screening tool to identify multiple LCT/MCM6 variants in a rapid manner. It overcomes diagnostic pitfalls that were reported and allows the simultaneous genotyping of closely spaced LCT variant sites in a single-step diagnostic approach.
    Clinica Chimica Acta 07/2008; 392(1-2):58-62. · 2.54 Impact Factor
  • Article: Mouse models of rhinovirus-induced disease and exacerbation of allergic airway inflammation.
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    ABSTRACT: Rhinoviruses cause serious morbidity and mortality as the major etiological agents of asthma exacerbations and the common cold. A major obstacle to understanding disease pathogenesis and to the development of effective therapies has been the lack of a small-animal model for rhinovirus infection. Of the 100 known rhinovirus serotypes, 90% (the major group) use human intercellular adhesion molecule-1 (ICAM-1) as their cellular receptor and do not bind mouse ICAM-1; the remaining 10% (the minor group) use a member of the low-density lipoprotein receptor family and can bind the mouse counterpart. Here we describe three novel mouse models of rhinovirus infection: minor-group rhinovirus infection of BALB/c mice, major-group rhinovirus infection of transgenic BALB/c mice expressing a mouse-human ICAM-1 chimera and rhinovirus-induced exacerbation of allergic airway inflammation. These models have features similar to those observed in rhinovirus infection in humans, including augmentation of allergic airway inflammation, and will be useful in the development of future therapies for colds and asthma exacerbations.
    Nature medicine 03/2008; 14(2):199-204. · 27.14 Impact Factor
  • Article: Pitfalls in LightCycler diagnosis of the single-nucleotide polymorphism 13.9 kb upstream of the lactase gene that is associated with adult-type hypolactasia.
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    ABSTRACT: Patients presenting with symptoms of lactose intolerance are in some centres routinely tested for a single-nucleotide polymorphism C-13910T, which is located upstream of the lactase gene (LCT) and is tightly associated with genetically determined lactase persistence/non-persistence. Typing of this polymorphism enables differential diagnosis for genetic versus secondary causes of lactose intolerance. Several PCR-based methods have been established as tests for this SNP. In particular, automated genotyping assays conducted on LightCycler platforms provide a rapid, labour-saving means for routine high-throughput analysis of this variant. Recently, several novel allelic variants have been identified in non-European populations. Three of these variants occur in close proximity to C-13910T, but their effect on the genetic test is unknown. Here we analyse whether the occurrence of C-13907G, T-13913C, and T-13915G, affect the diagnostic accuracy of C-13910T typings obtained using the LightCycler MutaREAL lactase real-time PCR kit. Genotyping of DNA samples harbouring respective variants or combinations thereof significantly influenced the LightCycler analysis. Some allelic combinations generated melting profiles that prevented the correct assignment of C-13910T. We conclude that genotyping of the C-13910T variant with the MutaREAL lactase real-time PCR kit in non-Europeans is prone to error and should be omitted.
    Clinica Chimica Acta 10/2007; 384(1-2):93-8. · 2.54 Impact Factor
  • Article: A novel polymorphism associated with lactose tolerance in Africa: multiple causes for lactase persistence?
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    ABSTRACT: Persistence or non-persistence of lactase expression into adult life is a polymorphic trait that has been attributed to a single nucleotide polymorphism (C-13910T) in an enhancer element 13.9 kb upstream of the lactase gene (LCT). The -13910*T allele occurs at very high frequency in northern Europeans as part of a very long haplotype (known as A), and promotes binding of the transcription factor Oct-1. However, -13910*T is at very low frequency in many African milk drinking pastoralist groups where lactase persistence phenotype has been reported at high frequency. We report here for the first time, a cohort study of lactose digester and non-digester Sudanese volunteers and show there is no association of -13910*T or the A haplotype with lactase persistence. We support this finding with new genotype/phenotype frequency comparisons in pastoralist groups of eastern African and Middle Eastern origin. Resequencing revealed three new SNPs in close proximity to -13910*T, two of which are within the Oct-1 binding site. The most frequent of these (-13915*G) is associated with lactose tolerance in the cohort study, providing evidence for a cis-acting effect. Despite its location, -13915*G abolishes, rather than enhances Oct-1 binding, indicating that this particular interaction is unlikely to be involved in lactase persistence. This study reveals the complexity of this phenotypic polymorphism and highlights the limitations of C-13910T as a diagnostic test for lactase persistence status, at least for people with non-European ancestry.
    Human Genetics 03/2007; 120(6):779-88. · 5.07 Impact Factor
  • Article: Alpha1-antitrypsin as a risk for infant and adult respiratory outcomes in a national birth cohort.
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    ABSTRACT: Reduced alpha1-antitrypsin (AAT) encoded by the gene SERPINA1 is a potential risk for pulmonary disease. We investigated SERPINA1 polymorphism as a risk for infant and adult pulmonary morbidity, and adult respiratory function and its change between 43 and 53 yr. We used data on a British national representative sample (n = 5,362) studied since birth in 1946 to age 53 yr (when n = 3,035), when DNA was first obtained. SERPINA1 Z and, to a lesser extent, S carriers had an increased risk of infant lower respiratory infection compared with those who were neither S nor Z carriers (Z carriers: odds ratio = 2.32, 95% confidence interval = 1.37-3.92; S but not Z carriers odds ratio = 1.58, 95% confidence interval = 1.10-2.28) after adjustment for environmental, socioeconomic, and developmental factors, and breast-feeding. There was no difference in the adult outcomes at 53 yr according to genotype, nor was there any association of genotype with change in forced expiratory volume at 1 s between 43 and 53 yr. Lower alpha1-antitrypsin, as indicated by carrier status for the Z and S alleles, was a risk for infant lower respiratory infection, but not for adult respiratory outcomes.
    American Journal of Respiratory Cell and Molecular Biology 12/2004; 31(5):559-64. · 5.13 Impact Factor
  • Article: The complete genomic organization of the human MUC6 and MUC2 mucin genes.
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    ABSTRACT: The complete genomic organization of the two mucin genes MUC2 and MUC6 was obtained by comparison of new and published mRNA sequences with newly available human genomic sequence. The two genes are located 38.5 kb apart in a head-to-head orientation within a gene complex on chromosome 11p15.5. The N-terminal organization of MUC6 is highly similar to that of MUC2, containing the D1, D2, D', and D3 Von Willebrand factor domains followed by the large tandem repeat domains located in exons 31 and 30, respectively. MUC6 has a much smaller C-terminal domain (101 amino acids) encoded by 2 exons containing only the CK domain, compared with MUC2, which has a C-terminal domain of 859 amino acids containing the D4, C, D, and CK domains, encoded by 19 exons. The gene structures agreed partially but not completely with predictions from gene prediction programs.
    Genomics 06/2004; 83(5):936-9. · 3.02 Impact Factor
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    Article: The T allele of a single-nucleotide polymorphism 13.9 kb upstream of the lactase gene (LCT) (C-13.9kbT) does not predict or cause the lactase-persistence phenotype in Africans.
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    ABSTRACT: The ability to digest the milk sugar lactose as an adult (lactase persistence) is a variable genetic trait in human populations. The lactase-persistence phenotype is found at low frequencies in the majority of populations in sub-Saharan Africa that have been tested, but, in some populations, particularly pastoral groups, it is significantly more frequent. Recently, a CT polymorphism located 13.9 kb upstream of exon 1 of the lactase gene (LCT) was shown in a Finnish population to be closely associated with the lactase-persistence phenotype (Enattah et al. 2002). We typed this polymorphism in 1,671 individuals from 20 distinct cultural groups in seven African countries. It was possible to match seven of the groups tested with groups from the literature for whom phenotypic information is available. In five of these groups, the published frequencies of lactase persistence are >/=25%. We found the T allele to be so rare that it cannot explain the frequency of the lactase-persistence phenotype throughout Africa. By use of a statistical procedure to take phenotyping and sampling errors into account, the T-allele frequency was shown to be significantly different from that predicted in five of the African groups. Only the Fulbe and Hausa from Cameroon possessed the T allele at a level consistent with phenotypic observations (as well as an Irish sample used for comparison). We conclude that the C-13.9kbT polymorphism is not a predictor of lactase persistence in sub-Saharan Africans. We also present Y-chromosome data that are consistent with previously reported evidence for a back-migration event into Cameroon, and we comment on the implications for the introgression of the -13.9kb*T allele.
    The American Journal of Human Genetics 06/2004; 74(6):1102-10. · 10.60 Impact Factor
  • Article: Hypervariability of the membrane-associated mucin and cancer marker MUC1.
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    ABSTRACT: The highly heterogeneous epithelial mucins show considerable inter-individual variability attributable to allelic variations in their tandem repeat (TR) peptide domains. Most mucins are known to show variations in repeat number but variation in the sequence of the individual TRs is not as well characterised. Here, we have studied variation in the immunodominant PDTR motif in the TR domain of the membrane-associated "cancer" mucin MUC1 by using the Minisatellite Variant Repeat-Polymerase chain reaction (MVR-PCR) technique. We have fully or partially mapped two nucleotide changes that encode two amino-acid changes, PDTR to PESR, across the arrays of 149 alleles. A total of 103 different maps was obtained when these changes alone were considered and additional variations were also observed. Most maps showed blocks of PDTR repeats interspersed with PESR repeats, although these were possibly more irregular in the longer alleles that also tended to have more PESR repeats. This variability has potential functional consequences and possible implications for some individuals with respect to the efficacy of immune targetting and immune therapy.
    Human Genetics 12/2003; 113(6):473-9. · 5.07 Impact Factor
  • Article: Aberrant expression of MUC3 and MUC4 membrane-associated mucins and sialyl Le(x) antigen in pancreatic intraepithelial neoplasia.
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    ABSTRACT: Ductal adenocarcinoma of the pancreas has recently been suggested to arise from histologically identifiable ductal lesions known as pancreatic intraepithelial neoplasia (PanINs). Altered levels and patterns of mucin gene expression have been reported to occur in epithelial cancers. To examine the pattern of expression of membrane-associated mucins, MUC3 and MUC4, and a mucin-associated carbohydrate tumor antigen, sialyl Le(x), in these precursor lesions and ductal adenocarcinoma of the pancreas. A total of 144 PanIN lesions and 85 cases of ductal adenocarcinoma of the pancreas were examined by using immunohistochemistry and in situ hybridization methods. MUC3 showed a progressive increase in expression in PanINs of increasing dysplasia and was also highly expressed in ductal adenocarcinoma. In contrast, neoexpression of MUC4 and sialyl Le(x) antigen was observed, mainly in PanIN-3 and ductal adenocarcinoma. In addition, a decrease in the expression of MUC3 and MUC4 was correlated with the degree of de-differentiation of the tumor. Aberrant expression of membrane mucins MUC3 and MUC4 and of a mucin-associated carbohydrate tumor antigen Sialyl Le(x) in PanINs and adenocarcinoma further supports the progression model for pancreatic adenocarcinoma.
    Pancreas 05/2003; 26(3):e48-54. · 2.39 Impact Factor
  • Article: Aberrant Expression of MUC3 and MUC4 Membrane-Associated Mucins and Sialyl Lex Antigen in Pancreatic Intraepithelial Neoplasia
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    ABSTRACT: Introduction: Ductal adenocarcinoma of the pancreas has recently been suggested to arise from histologically identifiable ductal lesions known as pancreatic intraepithelial neoplasia (PanINs). Altered levels and patterns of mucin gene expression have been reported to occur in epithelial cancers. Aim: To examine the pattern of expression of membrane-associated mucins, MUC3 and MUC4, and a mucin-associated carbohydrate tumor antigen, sialyl Lex, in these precursor lesions and ductal adenocarcinoma of the pancreas. Methodology: A total of 144 PanIN lesions and 85 cases of ductal adenocarcinoma of the pancreas were examined by using immunohistochemistry and in situ hybridization methods. Results: MUC3 showed a progressive increase in expression in PanINs of increasing dysplasia and was also highly expressed in ductal adenocarcinoma. In contrast, neoexpression of MUC4 and sialyl Lex antigen was observed, mainly in PanIN-3 and ductal adenocarcinoma. In addition, a decrease in the expression of MUC3 and MUC4 was correlated with the degree of de-differentiation of the tumor. Conclusion: Aberrant expression of membrane mucins MUC3 and MUC4 and of a mucin-associated carbohydrate tumor antigen Sialyl Lex in PanINs and adenocarcinoma further supports the progression model for pancreatic adenocarcinoma.
    Pancreas 03/2003; 26(3):e48-e54. · 2.39 Impact Factor

Institutions

  • 2012
    • The University of Manchester
      • Wellcome Trust Centre for Cell-Matrix Research
      Manchester, ENG, United Kingdom
  • 1999–2011
    • University College London
      • Department of Genetics, Evolution and Environment (GEE)
      London, ENG, United Kingdom
  • 2007
    • University Hospital RWTH Aachen
      Aachen, North Rhine-Westphalia, Germany