OCA2 gene controls brown and blue eye color. Other loci shape eye color hues in Europeans. Microsatellite linkage identifies eye color genes. Pigmentation candidate gene polymorphisms tested for eye color. Ancestry-informative SNPs analyze eye color genetics. Eye color shows strong heritability. Brown eye color gene BEY2 maps to chromosome 15q. OCA2 equals human P gene for pigmentation. MC1R interacts with OCA2 on pigmentation. Agouti signaling protein polymorphism affects iris color. Admixture mapping detects eye color linkages in populations. Iris melanocyte numbers differ in Asians, African-Americans, Caucasians.