#PAGE_PARAMS# #ADS_HEAD_SCRIPTS# #MICRODATA#

Enhanced Statistical Tests for GWAS in Admixed Populations: Assessment using African Americans from CARe and a Breast Cancer Consortium


While genome-wide association studies (GWAS) have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD) exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD) due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously considered SNP association (LD mapping) or admixture association (mapping by admixture-LD), but not both. Here, we introduce a new statistical framework for combining SNP and admixture association in case-control studies, as well as methods for local ancestry-aware imputation. We illustrate the gain in statistical power achieved by these methods by analyzing data of 6,209 unrelated African Americans from the CARe project genotyped on the Affymetrix 6.0 chip, in conjunction with both simulated and real phenotypes, as well as by analyzing the FGFR2 locus using breast cancer GWAS data from 5,761 African-American women. We show that, at typed SNPs, our method yields an 8% increase in statistical power for finding disease risk loci compared to the power achieved by standard methods in case-control studies. At imputed SNPs, we observe an 11% increase in statistical power for mapping disease loci when our local ancestry-aware imputation framework and the new scoring statistic are jointly employed. Finally, we show that our method increases statistical power in regions harboring the causal SNP in the case when the causal SNP is untyped and cannot be imputed. Our methods and our publicly available software are broadly applicable to GWAS in admixed populations.


Vyšlo v časopise: Enhanced Statistical Tests for GWAS in Admixed Populations: Assessment using African Americans from CARe and a Breast Cancer Consortium. PLoS Genet 7(4): e32767. doi:10.1371/journal.pgen.1001371
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1001371

Souhrn

While genome-wide association studies (GWAS) have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD) exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD) due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously considered SNP association (LD mapping) or admixture association (mapping by admixture-LD), but not both. Here, we introduce a new statistical framework for combining SNP and admixture association in case-control studies, as well as methods for local ancestry-aware imputation. We illustrate the gain in statistical power achieved by these methods by analyzing data of 6,209 unrelated African Americans from the CARe project genotyped on the Affymetrix 6.0 chip, in conjunction with both simulated and real phenotypes, as well as by analyzing the FGFR2 locus using breast cancer GWAS data from 5,761 African-American women. We show that, at typed SNPs, our method yields an 8% increase in statistical power for finding disease risk loci compared to the power achieved by standard methods in case-control studies. At imputed SNPs, we observe an 11% increase in statistical power for mapping disease loci when our local ancestry-aware imputation framework and the new scoring statistic are jointly employed. Finally, we show that our method increases statistical power in regions harboring the causal SNP in the case when the causal SNP is untyped and cannot be imputed. Our methods and our publicly available software are broadly applicable to GWAS in admixed populations.


Zdroje

1. AltshulerD

DalyMJ

LanderES

2008 Genetic mapping in human disease. Science 322 881 888

2. McCarthyMI

AbecasisGR

CardonLR

GoldsteinDB

LittleJ

2008 Genome-wide association studies for complex traits: consensus, uncertainty and challenges. Nat Rev Genet 9 356 369

3. AdeyemoA

GerryN

ChenG

HerbertA

DoumateyA

2009 A genome-wide association study of hypertension and blood pressure in African Americans. PLoS Genet 5 e1000564 doi:10.1371/journal.pgen.1000564

4. HancockDB

RomieuI

ShiM

Sienra-MongeJJ

WuH

2009 Genome-wide association study implicates chromosome 9q21.31 as a susceptibility locus for asthma in mexican children. PLoS Genet 5 e1000623 doi:10.1371/journal.pgen.1000623

5. SlatkinM

2008 Linkage disequilibrium—understanding the evolutionary past and mapping the medical future. Nat Rev Genet 9 477 485

6. SmithMW

O'BrienSJ

2005 Mapping by admixture linkage disequilibrium: advances, limitations and guidelines. Nat Rev Genet 6 623 632

7. PattersonN

HattangadiN

LaneB

LohmuellerKE

HaflerDA

2004 Methods for high-density admixture mapping of disease genes. Am J Hum Genet 74 979 1000

8. ZhuX

LukeA

CooperRS

QuertermousT

HanisC

2005 Admixture mapping for hypertension loci with genome-scan markers. Nat Genet 37 177 181

9. ReichD

PattersonN

De JagerPL

McDonaldGJ

WaliszewskaA

2005 A whole-genome admixture scan finds a candidate locus for multiple sclerosis susceptibility. Nat Genet 37 1113 1118

10. FreedmanML

HaimanCA

PattersonN

McDonaldGJ

TandonA

2006 Admixture mapping identifies 8q24 as a prostate cancer risk locus in African-American men. Proc Natl Acad Sci U S A 103 14068 14073

11. DeoRC

PattersonN

TandonA

McDonaldGJ

HaimanCA

2007 A high-density admixture scan in 1,670 African Americans with hypertension. PLoS Genet 3 e196 doi:10.1371/journal.pgen.0030196

12. NallsMA

WilsonJG

PattersonNJ

TandonA

ZmudaJM

2008 Admixture mapping of white cell count: genetic locus responsible for lower white blood cell count in the Health ABC and Jackson Heart studies. Am J Hum Genet 82 81 87

13. KaoWH

KlagMJ

MeoniLA

ReichD

Berthier-SchaadY

2008 MYH9 is associated with nondiabetic end-stage renal disease in African Americans. Nat Genet 40 1185 1192

14. ChengCY

KaoWH

PattersonN

TandonA

HaimanCA

2009 Admixture mapping of 15,280 African Americans identifies obesity susceptibility loci on chromosomes 5 and X. PLoS Genet 5 e1000490 doi:10.1371/journal.pgen.1000490

15. RischN

TangH

2006 Whole Genome Association Studies in Admixed Populations. Am J Hum Genet 79

16. WangK

ZhangH

KugathasanS

AnneseV

BradfieldJP

2009 Diverse genome-wide association studies associate the IL12/IL23 pathway with Crohn Disease. Am J Hum Genet 84 399 405

17. HayesMG

PluzhnikovA

MiyakeK

SunY

NgMC

2007 Identification of type 2 diabetes genes in Mexican Americans through genome-wide association studies. Diabetes 56 3033 3044

18. AltshulerDM

GibbsRA

PeltonenL

DermitzakisE

SchaffnerSF

2010 Integrating common and rare genetic variation in diverse human populations. Nature 467 52 58

19. ReichD

PriceAL

PattersonN

2008 Principal component analysis of genetic data. Nat Genet 40 491 492

20. PattersonN

PriceAL

ReichD

2006 Population structure and eigenanalysis. PLoS Genet 2 e190 doi:10.1371/journal.pgen.0020190

21. PriceAL

PattersonN

HancksDC

MyersS

ReichD

2008 Effects of cis and trans genetic ancestry on gene expression in African Americans. PLoS Genet 4 e1000294 doi:10.1371/journal.pgen.1000294

22. SmithMW

PattersonN

LautenbergerJA

TrueloveAL

McDonaldGJ

2004 A high-density admixture map for disease gene discovery in african americans. Am J Hum Genet 74 1001 1013

23. PriceAL

TandonA

PattersonN

BarnesKC

RafaelsN

2009 Sensitive detection of chromosomal segments of distinct ancestry in admixed populations. PLoS Genet 5 e1000519 doi:10.1371/journal.pgen.1000519

24. PasaniucB

SankararamanS

KimmelG

HalperinE

2009 Inference of locus-specific ancestry in closely related populations. Bioinformatics 25 i213 221

25. LettreG

PalmerCD

YoungT

EjebeKG

AllayeeH

2011 Genome-Wide Association Study of Coronary Heart Disease and Its Risk Factors in 8,090 African Americans: The NHLBI CARe Project. PLoS Genet 7 2 e1001300 doi:10.1371/journal.pgen.1001300

26. DevlinB

RoederK

1999 Genomic control for association studies. Biometrics 55 997 1004

27. FrazerKA

BallingerDG

CoxDR

HindsDA

StuveLL

2007 A second generation human haplotype map of over 3.1 million SNPs. Nature 449 851 861

28. MarchiniJ

HowieB

2010 Genotype imputation for genome-wide association studies. Nat Rev Genet 11 499 511

29. ZegginiE

ScottLJ

SaxenaR

VoightBF

MarchiniJL

2008 Meta-analysis of genome-wide association data and large-scale replication identifies additional susceptibility loci for type 2 diabetes. Nat Genet 40 638 645

30. RosenbergNA

HuangL

JewettEM

SzpiechZA

JankovicI

2010 Genome-wide association studies in diverse populations. Nat Rev Genet 11 356 366

31. HowieBN

DonnellyP

MarchiniJ

2009 A flexible and accurate genotype imputation method for the next generation of genome-wide association studies. PLoS Genet 5 e1000529 doi:10.1371/journal.pgen.1000529

32. BrowningBL

BrowningSR

2009 A unified approach to genotype imputation and haplotype-phase inference for large data sets of trios and unrelated individuals. Am J Hum Genet 84 210 223

33. HuangL

LiY

SingletonAB

HardyJA

AbecasisG

2009 Genotype-imputation accuracy across worldwide human populations. Am J Hum Genet 84 235 250

34. PasaniucB

AvineryR

GurT

SkibolaC

BracciP

2010 A Generic Coalescent-based Framework for the Selection of a Reference Panel for Imputation. Genetic Epidemiology

35. PasaniucB

KennedyJ

MandoiuI

2009 Imputation-based local ancestry inference in admixed populations. Proc 5th International Symposium on Bioinformatics Research and Applications 221 233

36. HunterDJ

KraftP

JacobsKB

CoxDG

YeagerM

2007 A genome-wide association study identifies alleles in FGFR2 associated with risk of sporadic postmenopausal breast cancer. Nat Genet 39 870 874

37. UdlerMS

MeyerKB

PooleyKA

KarlinsE

StruewingJP

2009 FGFR2 variants and breast cancer risk: fine-scale mapping using African American studies and analysis of chromatin conformation. Hum Mol Genet 18 1692 1703

38. ZaitlenN

PasaniucB

GurT

ZivE

HalperinE

2010 Leveraging genetic variability across populations for the identification of causal variants. Am J Hum Genet 86 23 33

39. CooperR

RotimiC

1997 Hypertension in blacks. Am J Hypertens 10 804 812

40. GillumRF

1996 The epidemiology of cardiovascular disease in black Americans. N Engl J Med 335 1597 1599

41. JonesDW

ChamblessLE

FolsomAR

HeissG

HutchinsonRG

2002 Risk factors for coronary heart disease in African Americans: the atherosclerosis risk in communities study, 1987-1997. Arch Intern Med 162 2565 2571

42. FreedlandSJ

IsaacsWB

2005 Explaining racial differences in prostate cancer in the United States: sociology or biology? Prostate 62 243 252

43. HarrisEL

ShermanSH

GeorgopoulosA

1999 Black-white differences in risk of developing retinopathy among individuals with type 2 diabetes. Diabetes Care 22 779 783

44. KjerulffKH

LangenbergP

SeidmanJD

StolleyPD

GuzinskiGM

1996 Uterine leiomyomas. Racial differences in severity, symptoms and age at diagnosis. J Reprod Med 41 483 490

45. MolokhiaM

HoggartC

PatrickAL

ShriverM

ParraE

2003 Relation of risk of systemic lupus erythematosus to west African admixture in a Caribbean population. Hum Genet 112 310 318

46. MarchiniJ

HowieB

MyersS

McVeanG

DonnellyP

2007 A new multipoint method for genome-wide association studies by imputation of genotypes. Nat Genet 39 906 913

47. GuanY

StephensM

2008 Practical issues in imputation-based association mapping. PLoS Genet 4 e1000279 doi:10.1371/journal.pgen.1000279

48. StephensM

BaldingDJ

2009 Bayesian statistical methods for genetic association studies. Nat Rev Genet 10 681 690

49. TeslovichTM

MusunuruK

SmithAV

EdmondsonAC

StylianouIM

2010 Biological, clinical and population relevance of 95 loci for blood lipids. Nature 466 707 713

50. PriceAL

PattersonNJ

PlengeRM

WeinblattME

ShadickNA

2006 Principal components analysis corrects for stratification in genome-wide association studies. Nat Genet 38 904 909

51. LiY

WillerC

SannaS

AbecasisG

2009 Genotype imputation. Annu Rev Genomics Hum Genet 10 387 406

52. PritchardJK

PrzeworskiM

2001 Linkage disequilibrium in humans: models and data. Am J Hum Genet 69 1 14

53. ZaitlenN

EskinE

2010 Imputation Aware Meta-Analysis of Genome Wide Association Studies. Genetic Epidemiology

54. KolonelLN

HendersonBE

HankinJH

NomuraAM

WilkensLR

2000 A multiethnic cohort in Hawaii and Los Angeles: baseline characteristics. Am J Epidemiol 151 346 357

55. MarchbanksPA

McDonaldJA

WilsonHG

BurnettNM

DalingJR

2002 The NICHD Women's Contraceptive and Reproductive Experiences Study: methods and operational results. Ann Epidemiol 12 213 221

56. AmbrosoneCB

CiupakGL

BanderaEV

JandorfL

BovbjergDH

2009 Conducting Molecular Epidemiological Research in the Age of HIPAA: A Multi-Institutional Case-Control Study of Breast Cancer in African-American and European-American Women. J Oncol 2009 871250

57. JohnEM

SchwartzGG

KooJ

WangW

InglesSA

2007 Sun exposure, vitamin D receptor gene polymorphisms, and breast cancer risk in a multiethnic population. Am J Epidemiol 166 1409 1419

58. JohnEM

HopperJL

BeckJC

KnightJA

NeuhausenSL

2004 The Breast Cancer Family Registry: an infrastructure for cooperative multinational, interdisciplinary and translational studies of the genetic epidemiology of breast cancer. Breast Cancer Res 6 R375 389

59. JohnEM

MironA

GongG

PhippsAI

FelbergA

2007 Prevalence of Pathogenic BRCA1 Mutation Carriers in 5 US Racial/Ethnic Groups. JAMA 298 2869 2876

60. NewmanB

MoormanPG

MillikanR

QaqishBF

GeradtsJ

1995 The Carolina Breast Cancer Study: integrating population-based epidemiology and molecular biology. Breast Cancer Res Treat 35 51 60

61. ProrokPC

AndrioleGL

BresalierRS

BuysSS

ChiaD

2000 Design of the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Control Clin Trials 21 273S 309S

62. ZhengW

CaiQ

SignorelloLB

LongJ

HargreavesMK

2009 Evaluation of 11 breast cancer susceptibility loci in African-American women. Cancer Epidemiol Biomarkers Prev 18 2761 2764

63. SmithTR

LevineEA

FreimanisRI

AkmanSA

AllenGO

2008 Polygenic model of DNA repair genetic polymorphisms in human breast cancer risk. Carcinogenesis 29 2132 2138

64. PalmerJR

WiseLA

HortonNJ

Adams-CampbellLL

RosenbergL

2003 Dual effect of parity on breast cancer risk in African-American women. J Natl Cancer Inst 95 478 483

65. RebbeckTR

TroxelAB

WalkerAH

PanossianS

GallagherS

2007 Pairwise combinations of estrogen metabolism genotypes in postmenopausal breast cancer etiology. Cancer Epidemiol Biomarkers Prev 16 444 450

Štítky
Genetika Reprodukčná medicína

Článok vyšiel v časopise

PLOS Genetics


2011 Číslo 4
Najčítanejšie tento týždeň
Najčítanejšie v tomto čísle
Kurzy

Zvýšte si kvalifikáciu online z pohodlia domova

Aktuální možnosti diagnostiky a léčby litiáz
nový kurz
Autori: MUDr. Tomáš Ürge, PhD.

Všetky kurzy
Prihlásenie
Zabudnuté heslo

Zadajte e-mailovú adresu, s ktorou ste vytvárali účet. Budú Vám na ňu zasielané informácie k nastaveniu nového hesla.

Prihlásenie

Nemáte účet?  Registrujte sa

#ADS_BOTTOM_SCRIPTS#