S Purcell

Summary

Affiliation: King's College London
Country: UK

Publications

  1. ncbi Variance components models for gene-environment interaction in quantitative trait locus linkage analysis
    Shaun Purcell
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College, London, UK
    Twin Res 5:572-6. 2002
  2. ncbi Variance components models for gene-environment interaction in twin analysis
    Shaun Purcell
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College, London, UK
    Twin Res 5:554-71. 2002
  3. ncbi A model-fitting implementation of the DeFries-Fulker model for selected twin data
    S Purcell
    Social, Genetic and Developmental Research Centre, Institute of Psychiatry, London SE5 8AF, UK
    Behav Genet 33:271-8. 2003
  4. ncbi Genetic Power Calculator: design of linkage and association genetic mapping studies of complex traits
    S Purcell
    Social, Genetics and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College London, De Crespigny Park, UK
    Bioinformatics 19:149-50. 2003
  5. ncbi Optimal sibship selection for genotyping in quantitative trait locus linkage analysis
    S Purcell
    Social, Genetic and Developmental Research Centre, 111 Denmark Hill, Denmark Hill, London SE5 8AF, UK
    Hum Hered 52:1-13. 2001
  6. ncbi Epistasis in quantitative trait locus linkage analysis: interaction or main effect?
    Shaun Purcell
    Social, Genetic, and Developmental Psychiatry Research Centre, Institute of Psychiatry, P O 080, King s College London, Denmark Hill, London SE5 8AF, United Kingdom
    Behav Genet 34:143-52. 2004
  7. pmc Power of linkage versus association analysis of quantitative traits, by use of variance-components models, for sibship data
    P C Sham
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London SE5 8AF, United Kingdom
    Am J Hum Genet 66:1616-30. 2000
  8. ncbi GENESiS: creating a composite index of the vulnerability to anxiety and depression in a community-based sample of siblings
    P C Sham
    Social, Genetic and Developmental Psychiatry Research Centre, London, UK
    Twin Res 3:316-22. 2000
  9. pmc Equivalence between Haseman-Elston and variance-components linkage analyses for sib pairs
    P C Sham
    Social, Genetic and Developmental Research Centre, Institute of Psychiatry, London, SE5 8AF, England
    Am J Hum Genet 68:1527-32. 2001
  10. ncbi A genome-wide scan of 1842 DNA markers for allelic associations with general cognitive ability: a five-stage design using DNA pooling and extreme selected groups
    R Plomin
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College London, UK
    Behav Genet 31:497-509. 2001

Collaborators

Detail Information

Publications52

  1. ncbi Variance components models for gene-environment interaction in quantitative trait locus linkage analysis
    Shaun Purcell
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College, London, UK
    Twin Res 5:572-6. 2002
    ..As well as elucidating environmental pathways, consideration of G x E in quantitative and molecular studies will potentially direct and enhance gene-mapping efforts...
  2. ncbi Variance components models for gene-environment interaction in twin analysis
    Shaun Purcell
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College, London, UK
    Twin Res 5:554-71. 2002
    ..As well as elucidating environmental pathways, consideration of gene-environment interaction in quantitative and molecular studies will potentially direct and enhance gene-mapping efforts...
  3. ncbi A model-fitting implementation of the DeFries-Fulker model for selected twin data
    S Purcell
    Social, Genetic and Developmental Research Centre, Institute of Psychiatry, London SE5 8AF, UK
    Behav Genet 33:271-8. 2003
    ..This more flexible implementation of the DF model allows DZ-O twins to be incorporated in a sex-limitation model. Brief simulation results are presented along with the Mx scripts used...
  4. ncbi Genetic Power Calculator: design of linkage and association genetic mapping studies of complex traits
    S Purcell
    Social, Genetics and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College London, De Crespigny Park, UK
    Bioinformatics 19:149-50. 2003
    ..A website for performing power calculations for the design of linkage and association genetic mapping studies of complex traits...
  5. ncbi Optimal sibship selection for genotyping in quantitative trait locus linkage analysis
    S Purcell
    Social, Genetic and Developmental Research Centre, 111 Denmark Hill, Denmark Hill, London SE5 8AF, UK
    Hum Hered 52:1-13. 2001
    ..In comparison to previous methods of selecting phenotypically extreme sibships for genotyping, the proposed method is considerably more efficient and is robust with regard to the specification of the genetic model...
  6. ncbi Epistasis in quantitative trait locus linkage analysis: interaction or main effect?
    Shaun Purcell
    Social, Genetic, and Developmental Psychiatry Research Centre, Institute of Psychiatry, P O 080, King s College London, Denmark Hill, London SE5 8AF, United Kingdom
    Behav Genet 34:143-52. 2004
    ..Second, because the nonepistatic variance component estimates in submodels can partially absorb epistatic variance when it is not explicitly modeled, power to formally detect epistasis is low...
  7. pmc Power of linkage versus association analysis of quantitative traits, by use of variance-components models, for sibship data
    P C Sham
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London SE5 8AF, United Kingdom
    Am J Hum Genet 66:1616-30. 2000
    ..We also describe both how the power of linkage is attenuated by incomplete linkage and incomplete marker information and how the power of association is attenuated by incomplete linkage disequilibrium...
  8. ncbi GENESiS: creating a composite index of the vulnerability to anxiety and depression in a community-based sample of siblings
    P C Sham
    Social, Genetic and Developmental Psychiatry Research Centre, London, UK
    Twin Res 3:316-22. 2000
    ..This index, which has a sib correlation of 0.22, will be used as a quantitative phenotype in the molecular genetic phase of GENESiS...
  9. pmc Equivalence between Haseman-Elston and variance-components linkage analyses for sib pairs
    P C Sham
    Social, Genetic and Developmental Research Centre, Institute of Psychiatry, London, SE5 8AF, England
    Am J Hum Genet 68:1527-32. 2001
    ..We show how this method can be used for both the selection of maximally informative sib pairs for genotyping and the subsequent analysis of such selected samples...
  10. ncbi A genome-wide scan of 1842 DNA markers for allelic associations with general cognitive ability: a five-stage design using DNA pooling and extreme selected groups
    R Plomin
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King s College London, UK
    Behav Genet 31:497-509. 2001
    ..Instead we are using the same design to screen markers such as cSNPs and SNPs in regulatory regions that are likely to include functional polymorphisms in which the marker can be presumed to be the QTL...
  11. ncbi Association analysis of monoamine genes with measures of depression and anxiety in a selected community sample of siblings
    M W Nash
    Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King s College London, London, United Kingdom
    Am J Med Genet B Neuropsychiatr Genet 135:33-7. 2005
    ..To our knowledge, this is the first study to report an association of the 3' end of TPH1 with continuous measures of depression and anxiety...
  12. ncbi The dopamine D4 receptor and the hyperactivity phenotype: a developmental-epidemiological study
    J S Mill
    Social, Genetic, and Developmental Psychiatry Research Centre, Institute of Psychiatry, London, SE5 8AF, UK
    Mol Psychiatry 7:383-91. 2002
    ..We found no evidence to support this association...
  13. ncbi The serotonin transporter gene as a QTL for ADHD
    Sarah Curran
    MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, De Crespigny Park, London, United Kingdom
    Am J Med Genet B Neuropsychiatr Genet 134:42-7. 2005
    ..0054 for the global test and an empirical P value = 0.00081 for the largest local test. Thus, we show here that SLC6A4, which has a major influence on brain serotonin availability, may be a QTL for ADHD...
  14. doi The positives, protocols, and perils of genome-wide association
    Benjamin M Neale
    Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King s College London, De Crespigny Park, London, UK
    Am J Med Genet B Neuropsychiatr Genet 147:1288-94. 2008
    ..We conclude with a look toward future developments such as the analysis of copy number variation and integration of expression and epigenetic phenomenon into genome-wide association...
  15. ncbi Direct or indirect association in a complex disease: the role of SLC22A4 and SLC22A5 functional variants in Crohn disease
    Sheila A Fisher
    Department of Medical and Molecular Genetics, King s College London School of Medicine, Guy s Hospital, London, United Kingdom
    Hum Mutat 27:778-85. 2006
    ....
  16. ncbi Population differences in the International Multi-Centre ADHD Gene Project
    Benjamin M Neale
    MRC Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King s College London, UK
    Genet Epidemiol 32:98-107. 2008
    ..Any case-control sample employing an Israeli sample with Northern Europeans must consider stratification. A Northern European tag set, however, appears to be appropriate for capturing the variation across populations...
  17. ncbi Family dysfunction interacts with genes in the causation of antisocial symptoms
    Tanya Maria May Button
    Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King s College, London, UK
    Behav Genet 35:115-20. 2005
    ..It was concluded that a risk genotype conferring susceptibility to family dysfunction is responsible for most of the variance in antisocial symptoms in childhood and adolescence...
  18. ncbi The relationship of fatigue to mental and physical health in a community sample
    Richard J Williamson
    Social, Genetic, Developmental Psychiatry Research, Institute of Psychiatry, PO80, 16 De Crespigny Park, Denmark Hill London SE5 8AF, UK
    Soc Psychiatry Psychiatr Epidemiol 40:126-32. 2005
    ..The present study seeks to differentiate between fatigue and depression/anxiety and to investigate the familiality/heritability of fatigue using sib-pairs...
  19. ncbi Optimal selection strategies for QTL mapping using pooled DNA samples
    Ansar Jawaid
    Department of Psychological Medicine, Institute of Psychiatry, King s College London, London SE5 8AF, UK
    Eur J Hum Genet 10:125-32. 2002
    ..Our results emphasize the importance of minimising experimental errors and suggest a pooling fraction of around 20%...
  20. ncbi Genome-wide linkage analysis of a composite index of neuroticism and mood-related scales in extreme selected sibships
    Matthew W Nash
    MRC Social, Genetic and Developmental Psychiatry Research Centre, Section of Epidemiology, Institute of Psychiatry, King s College, London, UK
    Hum Mol Genet 13:2173-82. 2004
    ..2) around 64 cM (43-70 cM) near marker D1S2892 and another on chromosome 6p (LOD 2.7) around 47 cM (34-63 cM) near marker D6S1610. Further exploratory sex-specific analyses suggested that these QTLs might have sex-limited effects...
  21. pmc Powerful regression-based quantitative-trait linkage analysis of general pedigrees
    Pak C Sham
    SGDP Research Centre, Institute of Psychiatry, King s College, Denmark Hill, London SE5 8AF, United Kingdom
    Am J Hum Genet 71:238-53. 2002
    ..In large sibships, the new method is slightly more powerful than variance-components models. The proposed method provides a practical and powerful tool for the linkage analysis of quantitative traits...
  22. ncbi Life events and depression in a community sample of siblings
    F V Rijsdijk
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London
    Psychol Med 31:401-10. 2001
    ..Appropriate modelling of life events in linkage and association analyses should help to identify QTLs for depression and anxiety...
  23. ncbi Genetic and environmental origins of verbal and performance components of cognitive delay in 2-year-olds
    T C Eley
    Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London, United Kingdom
    Dev Psychol 35:1122-31. 1999
    ..Because the genetic and environmental origins of V and P delays in infancy differ, they are better considered separately rather than combined into a composite measure of general cognitive delay...
  24. pmc PLINK: a tool set for whole-genome association and population-based linkage analyses
    Shaun Purcell
    Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
    Am J Hum Genet 81:559-75. 2007
    ..Analysis of the patterns of segmental sharing has the potential to map disease loci that contain multiple rare variants in a population-based linkage analysis...
  25. pmc Changing environmental influences on substance use across development
    Danielle M Dick
    Washington University, Department of Psychiatry, St Louis, MO 63110, USA
    Twin Res Hum Genet 10:315-26. 2007
    ..Furthermore, they illustrate the importance of using a developmental perspective to understand how specific influences may vary across different ages, and across different phenotypes...
  26. ncbi Association between treatment-emergent suicidal ideation with citalopram and polymorphisms near cyclic adenosine monophosphate response element binding protein in the STAR*D study
    Roy H Perlis
    Massachusetts General Hospital, Boston, MA 02114, USA
    Arch Gen Psychiatry 64:689-97. 2007
    ....
  27. doi 50bp deletion in the promoter for superoxide dismutase 1 (SOD1) reduces SOD1 expression in vitro and may correlate with increased age of onset of sporadic amyotrophic lateral sclerosis
    Wendy J Broom
    Day Neuromuscular Research Laboratory, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
    Amyotroph Lateral Scler 9:229-37. 2008
    ..Our findings suggest the hypothesis that this deletion reduces expression of the SOD1 gene and that levels of the SOD1 protein may modify the phenotype of SALS within selected populations...
  28. ncbi Contribution of methylenetetrahydrofolate reductase (MTHFR) polymorphisms to negative symptoms in schizophrenia
    Joshua L Roffman
    Schizophrenia Research Program, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
    Biol Psychiatry 63:42-8. 2008
    ..We examined whether the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C functional polymorphisms contribute to negative symptoms...
  29. pmc A second generation human haplotype map of over 3.1 million SNPs
    Kelly A Frazer
    The Scripps Research Institute, 10550 North Torrey Pines Road MEM275, La Jolla, California 92037, USA
    Nature 449:851-61. 2007
    ..Finally, we demonstrate increased differentiation at non-synonymous, compared to synonymous, SNPs, resulting from systematic differences in the strength or efficacy of natural selection between populations...
  30. pmc Genome-wide detection and characterization of positive selection in human populations
    Pardis C Sabeti
    Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02139, USA
    Nature 449:913-8. 2007
    ....
  31. pmc Two independent alleles at 6q23 associated with risk of rheumatoid arthritis
    Robert M Plenge
    Program in Medical and Population Genetics, Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
    Nat Genet 39:1477-82. 2007
    ..We show that these two SNP associations are statistically independent, are each reproducible in the comparison of our data and WTCCC data, and define risk and protective haplotypes for rheumatoid arthritis at 6q23...
  32. doi Family-based association study of lithium-related and other candidate genes in bipolar disorder
    Roy H Perlis
    Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, 185 Cambridge St, Boston, MA 02114, USA
    Arch Gen Psychiatry 65:53-61. 2008
    ..Recent developments suggest that a broader pool of genes may be associated with this disorder...
  33. doi Influence of RGS2 on anxiety-related temperament, personality, and brain function
    Jordan W Smoller
    Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
    Arch Gen Psychiatry 65:298-308. 2008
    ..The gene encoding regulator of G protein signaling 2 (Rgs2) is a quantitative trait gene that influences mouse anxiety behavior, making its human ortholog (RGS2) a compelling candidate gene for human anxiety phenotypes...
  34. doi Association of reading disability on chromosome 6p22 in the Afrikaner population
    Jill V Platko
    Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
    Am J Med Genet B Neuropsychiatr Genet 147:1278-87. 2008
    ..Of particular interest were markers on chromosomes 1 and 15. These two regions have been implicated in studies of populations that formed the founding population in the Afrikaner population...
  35. pmc Integrated genotype calling and association analysis of SNPs, common copy number polymorphisms and rare CNVs
    Joshua M Korn
    Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
    Nat Genet 40:1253-60. 2008
    ..The Birdsuite software is applied here to data from the Affymetrix SNP 6.0 array. Additionally, we describe a method, implemented in PLINK, to utilize these combined SNP and CNV genotypes for association testing with a phenotype...
  36. ncbi Genome-wide association analysis identifies loci for type 2 diabetes and triglyceride levels
    Richa Saxena
    Broad Institute of Harvard and Massachusetts Institute of Technology MIT, Cambridge, MA 02142, USA
    Science 316:1331-6. 2007
    ..The discovery of associated variants in unsuspected genes and outside coding regions illustrates the ability of genome-wide association studies to provide potentially important clues to the pathogenesis of common diseases...
  37. ncbi Investigation of parent-of-origin effects in ADHD candidate genes
    Jang Woo Kim
    Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
    Am J Med Genet B Neuropsychiatr Genet 144:776-80. 2007
    ..Thus, we conclude that a substantial parent-of-origin effect is unlikely for these leading ADHD candidate genes...
  38. ncbi Ascertainment through family history of disease often decreases the power of family-based association studies
    Manuel A R Ferreira
    Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, 185 Cambridge St, Boston, MA 02114, USA
    Behav Genet 37:631-6. 2007
    ..Our analytic approach to estimate the asymptotic power of the TDT is implemented online at http://pngu.mgh.harvard.edu/ ~purcell/gpc/...
  39. pmc Parental phenotypes in family-based association analysis
    Shaun Purcell
    Whitehead Institute for Biomedical Research, Cambridge, MA, USA
    Am J Hum Genet 76:249-59. 2005
    ..This methodology enables the extraction of more information from existing family-based collections that are currently being genotyped and analyzed by use of standard approaches...
  40. ncbi Environmental mediation and the twin design
    Shaun Purcell
    Psychiatry and Neurodevelopmental Genetics Unit, Center for Human Genetics Research, Massachusetts General Hospital, Boston, MA, USA
    Behav Genet 35:491-8. 2005
    ..Based on a simple simulation study, recommendations are given as to which methods should be applied and which should be avoided...
  41. pmc Replication of putative candidate-gene associations with rheumatoid arthritis in >4,000 samples from North America and Sweden: association of susceptibility with PTPN22, CTLA4, and PADI4
    Robert M Plenge
    Broad Institute of MIT and Harvard, Cambridge, MA, USA
    Am J Hum Genet 77:1044-60. 2005
    ....
  42. ncbi Properties of structured association approaches to detecting population stratification
    Shaun Purcell
    Whitehead Institute, Nine Cambridge Center, Cambridge, MA 02129, USA
    Hum Hered 58:93-107. 2004
    ..To examine the properties of the structured association approach for the detection and correction of population stratification...
  43. pmc Cannabis receptor haplotype associated with fewer cannabis dependence symptoms in adolescents
    Christian J Hopfer
    Department of Psychiatry, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
    Am J Med Genet B Neuropsychiatr Genet 141:895-901. 2006
    ..Our findings provide evidence suggesting that a common CNR1 haplotype is associated with developing fewer cannabis dependence symptoms among adolescents who have experimented with cannabis...
  44. ncbi Common variation in three genes, including a noncoding variant in CFH, strongly influences risk of age-related macular degeneration
    Julian Maller
    Center for Human Genetic Research, Massachusetts General Hospital, 185 Cambridge St, Boston, Massachusetts 02114, USA
    Nat Genet 38:1055-9. 2006
    ..Genotypes at these five common SNPs define a broad spectrum of interindividual disease risk and explain about half of the classical sibling risk of AMD in our study population...
  45. ncbi WHAP: haplotype-based association analysis
    Shaun Purcell
    Center for Human Genetic Research, MGH, Boston, MA, USA
    Bioinformatics 23:255-6. 2007
    ..We illustrate using these tests to dissect a multi-locus association...
  46. ncbi Identification of EFHC2 as a quantitative trait locus for fear recognition in Turner syndrome
    Lauren A Weiss
    Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
    Hum Mol Genet 16:107-13. 2007
    ..EFHC2 shows genealogy and extended LD consistent with directional selection. This novel QTL may influence social cognition in the general population and in autism...
  47. ncbi Clinical and genetic dissection of anger expression and CREB1 polymorphisms in major depressive disorder
    Roy H Perlis
    Depression Clinical and Research Program, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
    Biol Psychiatry 62:536-40. 2007
    ..Therefore, we examined the association between CREB1 polymorphisms and anger expression in MDD...
  48. ncbi Evaluation of common variants in the six known maturity-onset diabetes of the young (MODY) genes for association with type 2 diabetes
    Wendy Winckler
    Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
    Diabetes 56:685-93. 2007
    ..We conclude that although rare variants in these six genes explain most cases of MODY, common variants in these same genes contribute very modestly, if at all, to the common form of type 2 diabetes...
  49. ncbi Pretrauma cognitive ability and risk for posttraumatic stress disorder: a twin study
    William S Kremen
    Department of Psychiatry and Center for Behavioral Genomics, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
    Arch Gen Psychiatry 64:361-8. 2007
    ..Cognitive deficits are associated with posttraumatic stress disorder (PTSD), but whether such deficits reflect sequelae or risk factors is not fully resolved...
  50. pmc Two quantitative trait loci for prepulse inhibition of startle identified on mouse chromosome 16 using chromosome substitution strains
    Tracey L Petryshen
    Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, Broad Institute of Harvard, 185 Cambridge Street, Cambridge, MA 02139, USA
    Genetics 171:1895-904. 2005
    ..The regions contain a limited number of strong biological candidate genes that are potential risk genes for psychiatric disorders in which patients have PPI impairments...
  51. ncbi Effects of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on executive function in schizophrenia
    Joshua L Roffman
    Schizophrenia Research Program, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, USA
    Schizophr Res 92:181-8. 2007
    ..This study examined whether schizophrenia patients homozygous for the risk allele (T/T) exhibit greater impairment in executive function, and determined the extent to which MTHFR's effects on negative symptoms underlie this relationship...
  52. ncbi Domestic violence is associated with environmental suppression of IQ in young children
    Karestan C Koenen
    National Child Traumatic Stress Network, Department of Child and Adolescent Psychiatry, Boston University Medical Center, MA 02118, USA
    Dev Psychopathol 15:297-311. 2003
    ....