A H MacLennan

University of Adelaide, Tarndarnya, South Australia, Australia

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Publications (105)558.98 Total impact

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    ABSTRACT: Cerebral palsy (CP) is a common, clinically heterogeneous group of disorders affecting movement and posture. Its prevalence has changed little in 50 years and the causes remain largely unknown. The genetic contribution to CP causation has been predicted to be ~2%. We performed whole-exome sequencing of 183 cases with CP including both parents (98 cases) or one parent (67 cases) and 18 singleton cases (no parental DNA). We identified and validated 61 de novo protein-altering variants in 43 out of 98 (44%) case-parent trios. Initial prioritization of variants for causality was by mutation type, whether they were known or predicted to be deleterious and whether they occurred in known disease genes whose clinical spectrum overlaps CP. Further, prioritization used two multidimensional frameworks-the Residual Variation Intolerance Score and the Combined Annotation-dependent Depletion score. Ten de novo mutations in three previously identified disease genes (TUBA1A (n=2), SCN8A (n=1) and KDM5C (n=1)) and in six novel candidate CP genes (AGAP1, JHDM1D, MAST1, NAA35, RFX2 and WIPI2) were predicted to be potentially pathogenic for CP. In addition, we identified four predicted pathogenic, hemizygous variants on chromosome X in two known disease genes, L1CAM and PAK3, and in two novel candidate CP genes, CD99L2 and TENM1. In total, 14% of CP cases, by strict criteria, had a potentially disease-causing gene variant. Half were in novel genes. The genetic heterogeneity highlights the complexity of the genetic contribution to CP. Function and pathway studies are required to establish the causative role of these putative pathogenic CP genes.Molecular Psychiatry advance online publication, 10 February 2015; doi:10.1038/mp.2014.189.
    No preview · Article · Feb 2015 · Molecular Psychiatry
  • Michael O'Callaghan · Alastair Maclennan
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    ABSTRACT: To examine the association of cesarean delivery and cerebral palsy using a systematic literature review and meta-analysis. MEDLINE, Embase, and ClinicalTrials.gov were systematically searched for articles relating to cerebral palsy and cesarean delivery from inception until December 2012. Only articles reporting confirmed cases of cerebral palsy were included. Meta-analysis was used to assess combined results and also the following subgroups: emergency cesarean; elective cesarean; term delivery; preterm delivery; and delivery of breech-presenting newborns. Literature searches returned 1,874 articles with 58 considered in full. Studies were selected if they reported an endpoint of cerebral palsy, an intervention or risk of cesarean delivery, were in English, and gave sufficient details to perform meta-analysis. Nine case-control and four cohort studies were included in the overall analysis. Meta-analysis showed no overall association of cesarean delivery with cerebral palsy (odds ratio [OR] 1.29; 95% confidence interval [CI] 0.92-1.79; 3,810 case group participants and 1,692,580 control group participants). Emergency cesarean delivery was associated with increased risk of cerebral palsy (OR 2.17; 95% CI 1.58-2.98), whereas there was no significant association between elective cesarean delivery and cerebral palsy (OR 0.81; 95% CI 0.41-1.58). Any type of cesarean delivery (elective or emergency) for term newborns was associated with cerebral palsy (OR 1.6; 95% CI 1.05-2.44), whereas there was no association between any type of cesarean delivery and cerebral palsy in preterm newborns (OR 0.81; 95% CI 0.47-1.40). Cesarean delivery did not significantly modify cerebral palsy risk for breech-presenting newborns (OR 0.51; 95% CI 0.13-2.05). A review of the literature does not support the use of elective or emergency cesarean delivery to prevent cerebral palsy.
    No preview · Article · Nov 2013 · Obstetrics and Gynecology
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    ABSTRACT: Recent studies have established the role of rare copy number variants (CNVs) in several neurological disorders but the contribution of rare CNVs to cerebral palsy (CP) is not known. Fifty Caucasian families having children with CP were studied using two microarray designs. Potentially pathogenic, rare (<1% population frequency) CNVs were identified, and their frequency determined, by comparing the CNVs found in cases with 8329 adult controls with no known neurological disorders. Ten of the 50 cases (20%) had rare CNVs of potential relevance to CP; there were a total of 14 CNVs, which were observed in <0.1% (<8/8329) of the control population. Eight inherited from an unaffected mother: a 751-kb deletion including FSCB, a 1.5-Mb duplication of 7q21.13, a 534-kb duplication of 15q11.2, a 446-kb duplication including CTNND2, a 219-kb duplication including MCPH1, a 169-kb duplication of 22q13.33, a 64-kb duplication of MC2R, and a 135-bp exonic deletion of SLC06A1. Three inherited from an unaffected father: a 386-kb deletion of 12p12.2-p12.1, a 234-kb duplication of 10q26.13, and a 4-kb exonic deletion of COPS3. The inheritance was unknown for three CNVs: a 157-bp exonic deletion of ACOX1, a 693-kb duplication of 17q25.3, and a 265-kb duplication of DAAM1. This is the first systematic study of CNVs in CP, and although it did not identify de novo mutations, has shown inherited, rare CNVs involving potentially pathogenic genes and pathways requiring further investigation.European Journal of Human Genetics advance online publication, 22 May 2013; doi:10.1038/ejhg.2013.93.
    Full-text · Article · May 2013 · European journal of human genetics: EJHG
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    ABSTRACT: Arthrogryposis multiplex congenita (AMC) is caused by heterogeneous pathologies leading to multiple antenatal joint contractures through fetal akinesia. Understanding the pathophysiology of this disorder is important for clinical care of the affected individuals and genetic counseling of the families. We thus aimed to establish the genetic basis of an AMC subtype that is associated with multiple dysmorphic features and intellectual disability (ID). We used haplotype analysis, next-generation sequencing, array comparative genomic hybridization, and chromosome breakpoint mapping to identify the pathogenic mutations in families and simplex cases. Suspected disease variants were verified by cosegregation analysis. We identified disease-causing mutations in the zinc-finger gene ZC4H2 in four families affected by X-linked AMC plus ID and one family affected by cerebral palsy. Several heterozygous females were also affected, but to a lesser degree. Furthermore, we found two ZC4H2 deletions and one rearrangement in two female and one male unrelated simplex cases, respectively. In mouse primary hippocampal neurons, transiently produced ZC4H2 localized to the postsynaptic compartment of excitatory synapses, and the altered protein influenced dendritic spine density. In zebrafish, antisense-morpholino-mediated zc4h2 knockdown caused abnormal swimming and impaired α-motoneuron development. All missense mutations identified herein failed to rescue the swimming defect of zebrafish morphants. We conclude that ZC4H2 point mutations, rearrangements, and small deletions cause a clinically variable broad-spectrum neurodevelopmental disorder of the central and peripheral nervous systems in both familial and simplex cases of both sexes. Our results highlight the importance of ZC4H2 for genetic testing of individuals presenting with ID plus muscle weakness and minor or major forms of AMC.
    Full-text · Article · Apr 2013 · The American Journal of Human Genetics
  • B Purbrick · K Stranks · C Sum · A H MacLennan
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    ABSTRACT: The ideal long-term, randomized, placebo-controlled trial of hormone replacement therapy (HRT) from near menopause for up to 30 years to assess major morbidity and mortality is impractical because of high cost, participant retention, therapy compliance, and continuity of research staff and funding. Also the trial regimen may become outdated. It is nihilistic to demand such a long-term trial before endorsing HRT. However, medium-term trials using surrogate measures for long-term morbidity and mortality are possible and two are near completion. If these studies have been able to maintain reasonable participant retention, therapy compliance and minimal breach of protocol, they will set standards for trials of new HRT regimens. This paper discusses lessons learnt from past attempts at long-term trials and suggests the currently optimal protocol and cost of assessing new HRT regimens to optimize potential benefits and minimize adverse effects. A 5-7-year randomized, placebo-controlled trial of a flexible transdermal estrogen regimen ± either a selective estrogen receptor modulator, e.g. bazedoxifene, or micronized progesterone is discussed. Mild to moderately symptomatic women, 1-4 years post menopause, can be recruited via general practice and group meetings. Future trials should be funded by independent agencies and are high priority in women's health.
    No preview · Article · Jun 2012 · Climacteric
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    A Pines · D W Sturdee · A H MacLennan
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    ABSTRACT: The quality of life of countless menopausal women world-wide has been significantly diminished following the sensationalist reporting of the Women's Health Initiative (WHI) and the resulting 50% or more decline in the use of hormone replacement therapy (HRT) over the subsequent 10 years. Quality of life is difficult to measure as there are so many contributing factors and a large number of different instruments, some of which assess general health and only a few which specifically include symptoms related to menopause. HRT improves quality of life of symptomatic menopausal women and some studies of the effects of HRT provide reliable evidence on quality of life other than reduction in vasomotor symptoms. Until there is a better understanding of the minimal risks of HRT for the majority of women, too many will continue to suffer a reduced quality of life unnecessarily.
    Full-text · Article · Jun 2012 · Climacteric
  • H G Burger · A H MacLennan · K-E Huang · C Castelo-Branco
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    ABSTRACT: Following the announcement of the first results of the Women's Health Initiative (WHI) to the media in 2002, prior to their scientific publication, the resulting panic headlines had an immediate and lasting negative effect on use of menopausal hormone replacement therapy (HRT) around the world. Rates of use dropped by 40-80%. Symptomatic women then sought multiple alternative therapies but the majority of these have no greater effect than the effect seen from placebo in well-conducted trials of HRT. Some of these therapies have risks. Although anecdotally most menopause practitioners after 2002 can attest to having to counsel large numbers of women with debilitating menopausal symptoms who were too frightened to consider HRT, it is difficult to document loss of health-related quality of life in large population studies as they were not conducted. Similarly, the positive or negative effects of the marked decline in HRT on long-term morbidities and mortality have yet to be fully assessed. Recent studies have shown an increase in postmenopausal fractures and in some, but not all, populations a small temporary decline in breast cancer. Cardiovascular outcomes may not be apparent for another decade. Short-term, randomized, placebo-controlled trials confirm that HRT is the only therapy that effectively improves health-related quality of life in symptomatic women through a reduction in vasomotor and urogenital symptoms, joint pains and insomnia, while improving sexuality. The results of the re-analyses of the WHI data and new data from other studies do not justify the continuing negative attitude to HRT in symptomatic women who start HRT near menopause.
    No preview · Article · Jun 2012 · Climacteric
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    ABSTRACT: Objective: Intrauterine infection is a risk factor for cerebral palsy. Previous work reported a high frequency of viral DNA in newborn screening cards from cerebral palsy cases and controls possibly due to contamination. Methods: Retrospective case-control study using improved methodologies to minimize contamination during PCR-based detection of viral DNA sequences. Newborn screening cards of 339 Caucasian children with cerebral palsy and 594 controls were examined. Viruses tested were herpes simplex viruses 1 and 2 (HSV1 and 2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes viruses 6, 7 and 8 (HHV6, HHV7 and HHV8), and parvovirus B19. Genotyping was performed on DNA extracted from dried blood spots. Results: CMV and EBV were detected in 5 (1.5%) and 3 (0.9%) of 339 cases, respectively, but not in controls (p = 0.047 and 0.006). Frequencies of detection of the other viruses examined were similar for cases and controls. DNA from at least one of the nine viruses tested was found in 4.4% of cases and 3.1% of controls [OR 1.4 95% CI (0.71-2.76)]. Conclusion: Evidence of congenital viral infection was uncommon in cases of cerebral palsy and controls. However, CMV and EBV were significantly associated with cerebral palsy.
    Full-text · Article · Feb 2012 · The journal of maternal-fetal & neonatal medicine: the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians
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    ABSTRACT: ABSTRACT Objective An overview of the current knowledge on the etiology and treatment of vasomotor symptoms in postmenopausal women. Materials and methods Acknowledged experts in the field contributed a brief assessment of their areas of interest which were combined and edited into the final manuscript. Results Women around the world experience vasomotor symptoms as they enter and complete the menopause transition. Vasomotor symptoms, specifically hot flushes, are caused by a narrowing of the thermoneutral zone in the brain. This effect, although related to estrogen withdrawal, is most likely related to changes in central nervous system neurotransmitters. Peripheral vascular reactivity is also altered in symptomatic women. Estrogen replacement therapy is the most effective treatment for hot flushes. Of the other interventions investigated, selective serotonin and selective norepinephrine reuptake inhibitors and gabapentin show efficacy greater than placebo. Objective monitoring of hot flushes indicates a robust improvement with hormone replacement therapy but little to no change with placebo. These data suggest that the subjective assessment of responses to therapy for vasomotor symptom results in inaccurate data. Hot flushes have recently been associated with increased cardiovascular risks and a lower incidence of breast cancer, but these data require confirmation. Conclusions Vasomotor symptoms are experienced by women of all ethnic groups. They are caused by changes in the central nervous system associated with estrogen withdrawal and are best treated with estrogen replacement therapy. Objective monitoring of hot flushes indicates that placebo has little to no effect on their improvement. Subjective assessments of hot flushes in clinical trials may be inaccurate based on objective measurement of the frequency of hot flushes. Based on preliminary reports, women experiencing hot flushes have an increased risk of cardiovascular disease and a reduced incidence of breast cancer.
    Full-text · Article · Sep 2011 · Climacteric
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    Full-text · Article · Jun 2011 · Climacteric
  • A H MacLennan
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    ABSTRACT: Many traditional contraindications to hormone replacement therapy (HRT) are based on the theoretical potential for these hormones to worsen a disease process and are rarely based on supporting data. This review addresses the available data and lack of data that make the prescription of HRT difficult in a variety of common morbidities. In each circumstance, it is assumed that conservative evidence-based therapies have been tried and that menopausal symptoms remain debilitating and are reducing quality of life. Tailoring of the product, dose, route and regimen may avoid some of the theoretical risks of HRT in particular women or conditions and guidelines are given for each co-morbidity. Specifically, it is discussed that tailored HRT may be used without strong evidence of a deleterious effect after ovarian cancer, endometrial cancer, most other gynecological cancers, bowel cancer, melanoma, a family history of breast cancer, benign breast disease, in carriers of BRACA mutations, after breast cancer if adjuvant therapy is not being used, past thromboembolism, varicose veins, fibroids and past endometriosis. Relative contraindications are existing cardiovascular and cerebrovascular disease and breast cancer being treated with adjuvant therapies. Consultation with other carers and written consent are recommended in all these difficult circumstances, but no condition is an absolute contraindication to HRT if potential risk is understood, if HRT is effective in symptom control and if quality of remaining life is paramount.
    No preview · Article · Feb 2011 · Climacteric
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    ABSTRACT: IntroductionThe Australian Cerebral Palsy Research Study assessed established and novel epidemiological and genetic risk factors for cerebral palsy (CP) along with their interactions.Methods Epidemiological data were collected by maternal questionnaire and linkage to state-based perinatal repositories and CP registers. Buccal swabs from 587 case and 1154 control mother-child pairs provided DNA for assessment of 35 single nucleotide polymorphisms (SNPs).ResultsEpidemiological associations with CP included: maternal infection during pregnancy (OR 1.55, 95% CI 1.26 to 1.91), small for gestational age (
    No preview · Article · Jan 2011
  • Alastair MacLennan · David Sturdee · Anna Fenton · Nick Panay

    No preview · Article · Aug 2010 · Climacteric
  • A H MacLennan · T K Gill · J L Broadbent · A W Taylor
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    ABSTRACT: To describe the prevalence of menopausal hormone therapy (HT) in 2008 and trends over the last 17 years in an Australian population. Data were obtained from nine representative population face-to-face interview surveys of the South Australian population from 1991 to 2008. The surveys used consistent method and quality control procedures. In 2008, demographic data, HT use and eight dimensions of health, using the SF-36 health survey questionnaire, were measured. Participants Over 3000 South Australian adults were interviewed in their own home by trained health interviewers in each of the surveys; in the 2008 survey, 1555 women participated, of whom 953 were over age 40. After a peak in use in the 2000 survey, HT use fell from 2003 and has continued to decline in 2008. In 2008, current use over age 50 of registered conventional HT products is now 11.8%, with a further 4.0% using non-registered alternative 'hormonal' products. Current HT use is highest between the ages of 50 and 59 years, where 13.4% use conventional HT and 7.7% use unconventional alternative hormones. Use of these unregistered hormonal products was rare in previous surveys. Median and mean length of conventional HT use were 10.0 and 10.5 years, respectively. HT users continued to have a demographic profile similar to those in previous surveys, i.e. they were better educated, employed, partnered, had a higher income and were less inclined to use complementary and alternative medicines. There has been a continuing decline in both the overall prevalence and length of use of conventional HT from 2003, probably in association with negative media about HT. Of medical concern is that about one-quarter of women using HT around menopause now chooses unregistered hormonal mixtures that are untested for long-term safety and efficacy.
    No preview · Article · May 2009 · Climacteric
  • M E O'Callaghan · A H MacLennan · E A Haan · G Dekker
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    ABSTRACT: Cerebral palsy has been associated with a number of candidate genes. To date, no systematic review has been conducted to synthesise genetic polymorphism associations with cerebral palsy. We apply the HuGE NET guidelines to search PubMed and EMBASE databases for publications investigating single nucleotide polymorphisms (SNPs) and cerebral palsy outcome. 22 papers were identified and are discussed in this review. Candidate genes were grouped as (1) thrombophilic, (2) cytokine, (3) apolipoprotein E or (4) other SNPs, largely related to cardiovascular physiology/pathophysiology and the functioning of the immune system. Of the studies identified, cohorts were usually small, without adequate control and ethnically diverse, making direct comparison between studies difficult. The most promising candidate genes include factor V Leiden, methylenetetrahydrofolate reductase, lymphotoxin-alpha, tumour necrosis factor-alpha, eNOS and mannose binding lectin. Large case-control studies are needed to confirm these candidates with attention given to cohort ethnicity, cerebral palsy subtype analysis and possible multiple gene and gene-environment interactions.
    No preview · Article · Mar 2009 · Human Genetics
  • H P G Schneider · A H Maclennan · D Feeny
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    ABSTRACT: There is a great need for the accurate assessment of health-related quality of life (HRQOL) in clinical practice, research, health interventions and health planning. The menopause transition and special issues influencing the health of women as they age can affect quality of life. The assessment of these effects requires a variety of validated instruments to capture their influence in a variety of populations and for a variety of outcomes. This review identifies the important measurement properties of HRQOL instruments, determinants of health status and the currently available measures of HRQOL. Specifically, the reliability, validity and applicability of HRQOL instruments designed for use at the climacteric are individually discussed. It is important to choose validated and appropriate instruments depending on the individual or population being assessed and the relevant HRQOL issues.
    No preview · Article · May 2008 · Climacteric
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    C S Gibson · P N Goldwater · A H MacLennan · EA Haan · K Priest · GA Dekker
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    ABSTRACT: To investigate the role of fetal viral infection in the development of a range of adverse pregnancy outcomes (APOs), including pregnancy-induced hypertensive disorders (PIHD), antepartum haemorrhage (APH), birthweight <10th percentile (small for gestational age, SGA) and preterm birth (PTB). Population-based case-control study. Laboratory-based study. The newborn screening cards of 717 adverse pregnancy cases and 609 controls. Newborn screening cards were tested for RNA from enteroviruses and DNA from herpesviruses using polymerase chain reaction (PCR). The herpesviruses were detected using two PCRs, one detecting nucleic acids from herpes simplex virus (HSV)-1, HSV-2, Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpesvirus (HHV)-8, hereafter designated Herpes PCR group A viruses, and the other detecting nucleic acids from varicella-zoster virus (VZV), HHV-6 and HHV-7, hereafter designated Herpes PCR group B viruses. Odds ratios and 95% CIs for specific APOs. For both term and PTBs, the risk of developing PIHD was increased in the presence of DNA from Herpes PCR group B viruses (OR 3.57, 95% CI 1.10-11.70), CMV (OR 3.89, 95% CI 1.67-9.06), any herpesvirus (OR 5.70, 95% CI 1.85-17.57) and any virus (OR 5.17, 95% CI 1.68-15.94). The presence of CMV was associated with PTB (OR 1.61, 95% CI 1.14-2.27). No significant association was observed between SGA or APH and exposure to viral infection. Fetal exposure to herpesvirus infection was associated with PIHD for both term and PTBs in this exploratory study. Exposure to CMV may also be associated with PTB. These findings need confirmation in future studies.
    Full-text · Article · Mar 2008 · BJOG An International Journal of Obstetrics & Gynaecology

  • No preview · Article · Dec 2007 · American Journal of Obstetrics and Gynecology

  • No preview · Article · Jan 2006

  • No preview · Article · Dec 2005 · American Journal of Obstetrics and Gynecology

Publication Stats

3k Citations
558.98 Total Impact Points

Institutions

  • 1980-2015
    • University of Adelaide
      • • Robinson Institute
      • • Discipline of Obstetrics and Gynaecology
      Tarndarnya, South Australia, Australia
  • 2000
    • Women`s and Children`s Hospital
      Tarndarnya, South Australia, Australia
  • 1995
    • University of Otago
      Taieri, Otago, New Zealand
  • 1987
    • The Queen Elizabeth Hospital
      • Department of Obstetrics and Gynaecology
      Tarndarnya, South Australia, Australia