Estimating ethnic admixture from pedigree data.
This paper introduces a likelihood method of estimating ethnic admixture that uses individuals, pedigrees, or a combination of individuals and pedigrees. For each founder of a pedigree, admixture proportions are calculated by conditioning on the pedigree-wide genotypes at all ancestry-informative markers. These estimates are then propagated down the pedigree to the nonfounders by a simple averaging process. The large-sample standard errors of the founders' proportions can be similarly transformed into standard errors for the admixture proportions of the descendants. These standard errors are smaller than the corresponding standard errors when each individual is treated independently. Both hard and soft information on a founder's ancestry can be accommodated in this scheme, which has been implemented in the genetic software package Mendel. The utility of the method is demonstrated on simulated data and a real data example involving Mexican families of mixed Amerindian and Spanish ancestry.
Sinsheimer
Janet S
JS
Department of Human Genetics, The University of California, Los Angeles, CA 90095, USA. janet@mednet.ucla.edu
Plaisier
Christopher L
CL
Huertas-Vazquez
Adriana
A
Aguilar-Salinas
Carlos
C
Tusie-Luna
Teresa
T
Pajukanta
Päivi
P
Lange
Kenneth
K
D003198:Computer Simulation; D005006:Ethnicity / Q000235:genetics*; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D016013:Likelihood Functions; D008800:Mexico / Q000208:ethnology; D010375:Pedigree; D012984:Software
D005819:Genetic Markers