Admixture in the Hispanics of the San Luis Valley, Colorado, and its implications for complex trait gene mapping.
Hispanic populations are a valuable resource that can and should facilitate the identification of complex trait genes by means of admixture mapping (AM). In this paper we focus on a particular Hispanic population living in the San Luis Valley (SLV) in Southern Colorado. We used a set of 22 Ancestry Informative Markers (AIMs) to describe the admixture process and dynamics in this population. AIMs are defined as genetic markers that exhibit allele frequency differences between parental populations >or=30%, and are more informative for studying admixed populations than random markers. The ancestral proportions of the SLV Hispanic population are estimated as 62.7 +/- 2.1% European, 34.1 +/- 1.9% Native American and 3.2 +/- 1.5% West African. We also estimated the ancestral proportions of individuals using these AIMs. Population structure was demonstrated by the excess association of unlinked markers, the correlation between estimates of admixture based on unlinked marker sets, and by a highly significant correlation between individual Native American ancestry and skin pigmentation (R2= 0.082, p < 0.001). We discuss the implications of these findings in disease gene mapping efforts.
National Human Genome Center, Howard University, Washington, DC 20060, USA. cbonliia@genomecenter.howard.edu
C
C
Bonilla
E J
EJ
Parra
C L
CL
Pfaff
S
S
Dios
J A
JA
Marshall
R F
RF
Hamman
R E
RE
Ferrell
C L
CL
Hoggart
P M
PM
McKeigue
M D
MD
Shriver
D000328:Adult; D000368:Aged; D002874:Chromosome Mapping; D003120:Colorado; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D005828:Genetics, Population; D006630:Hispanic or Latino / Q000235:genetics*; D006801:Humans; D007198:Indians, North American / Q000235:genetics; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D020412:Multifactorial Inheritance; D011110:Polymorphism, Genetic; D019655:Quantitative Trait, Heritable; D012880:Skin Pigmentation / Q000235:genetics
D005819:Genetic Markers