Yorgov et al. [2013] performed association and admixture mapping of the real SBP and DBP phenotypes on chromosome 3 with the sequencing data. The following four nested linear regression models were considered, where all of the models included global ancestry on chromosome 3 as a covariate: model 1 (null model); model 2 included the SNP genotype as a predictor; model 3 included estimates of local European, Native American, and African ancestry at a SNP as predictors; and model 4 included both genotype and local ancestry at the SNP as predictors, which allows for the population specific genetic association effects at a SNP based on local ancestry. Wald and likelihood ratio tests were used to test association (model 2 versus model 1); admixture (model 3 versus model 1); association adjusted for admixture (model 4 versus model 3); and admixture and/or association (model 4 versus model 1).
