The samples were genotyped for 186 ancestry markers (AIMS) (43). The same AIMs were genotyped in 1051 individuals from the 51 worldwide populations represented in the HGDP-CEPH Human Genome Diversity Cell Line Panel (http://www.cephb.fr/HGDP-CEPH-Panel). Structure 2.2 (http://pritch.bsd.uchicago.edu/software.html) was run simultaneously using the AIMS genotypes from our sample and the 51 CEPH populations to identify population substructure and compute individual ethnic factor scores. This ancestry assessment identifies seven ethnic factors (43). In our study sample the predominant mean (median) ethnic factor scores were: African: 0.77 (0.81); European: 0.09 (0.04); Mid East and Asian: 0.06 (0.04).
