COMBINATIONAL VARIATION OF SNP ALLELES AT MULTIPLE LOCI CONTRIBUTE TO SKIN COLOR DIFFERENCE BETWEEN CAUCASOID AND MONGOLOID

Abstract

This study aims to identify Single Nucleotide Polymorphisms (SNP) alleles at multiple loci associated with racial differences in skin color using SNP genotyping. A total of 122 Caucasians living in Toledo, Ohio and 100 Japanese were genotyped for the 20 SNPs in the 7 candidate genes. Data obtained from the SNP genotyping were used to analyze associations of the 20 SNP alleles by use of linkage disequilibrium (LD). Combinations of SNP alleles under LD were jointly tested for association with the racial groups by performing a χ^2 test for independence. Results show that the SNP alleles at the multiple loci considered as the haplotype contribute to the differences while suggesting a high probability of LD. Confirmation of these findings requires further study with other ethnic groups to analyze the associations between SNP alleles at multiple loci and racial skin color variation.