Variants of the melanocortin 1 receptor gene (MC1R) and P gene as indicators of the population origin of an individual

Abstract

The population origin of an individual is often requested to be determined from specimens left at a crime scene for identifying a suspect and individual identity. The melanocortin 1 receptor gene (MC1R) and P gene are associated with human pigmentation. Although several studies have reported that these genes are highly polymorphic in human populations, it is unclear if the allele variants can be used to determine the population origin of an individual. We aimed to determine the ethnic origin of an individual by using single nucleotide polymorphisms (SNPs). Eighteen SNPs in the MC1R gene and P genes were genotyped in 52 individuals by the direct sequencing method, and 4 SNPs (MC1R gene: R163Q and P gene: IVS5 + 1001, IVS13 + 113, and H615R) were selected on the basis of differences in frequencies. Subsequently, we genotyped these four SNPs in 422 volunteers from six ethnically defined populations using a polymerase chain reaction-based assay. The results revealed that the allele variants were present with high frequencies in Asian populations but were low in European and African populations. On the basis of these results, we defined a specific combination of a genotype (R163Q) and a diplotype group (IVS5 + 1001, IVS13 + 113, and H615R). This study indicates that the specific combination of a genotype and a diplotype group would be effective in estimating the population origin of an individual from a list of population groups.

The association between GAD1 gene polymorphisms and cerebral palsy in Chinese infants

“…However, no marked linkage disequilibrium was found between rs3791874 and rs16858977. Given this, we supposed that rs3791862 was a newly formed SNP and might evolve because of gene-tic drift or positive Darwinian selection [23,24]. According to this theory, the individuals with heterozygous status at rs3791862 should present a prominent linkage disequilibrium between rs3791874 and rs16858977 and our results verified the hypothesis (D = 0.95).…”

MC1R variants and associations with pigmentation characteristics and genetic ancestry in a Hispanic, predominately Puerto Rican, population

“…One recent study set in New Mexico reported carriage of a medium or high risk MC1R variant in 63% of enrolled Hispanics 37 . Some studies have examined associations between MC1R variation and genetic ancestry 38,39 , but there appears to be limited research that also incorporates pigmentation characteristics in Hispanic populations. Our findings contribute novel evidence on the association between MC1R variation and pigmentation characteristics in Hispanics who were not selected to participate on the basis of their personal or family history of melanoma (or non-melanoma skin cancers).…”