HERC2 and OCA2 genes polimorphisms in relation to the iris color variation of the Belarusian population

The human genetic phenotyping is one of the most intensely developing area of forensic genetics. Externally visible traits, including eye color, can be predicted by analyzing single nucleotide polymorphisms with a high predictive rate. We studied the polymorphisms rs12913832 and rs1800407 in the HERC2 and OCA2 genes, respectively, to evaluate its prognostic availability in relation to the iris pigmentation of the Belarusian population. For this, both eye images and DNA samples were collected from 314 individuals to analyze the key polymorphisms by the TaqMan assay. Our data confirmed a relevance of rs12913832:A>G and rs1800407:G>A in the prediction context. The highest values of the sensitivity (SE = 0.94) and the specificity (SP = 0.90) were obtained for rs12913832, demonstrating the high efficiency of this marker as a classifier of phenotypic groups. The presence of the ancestral dominant allele rs12913832-A causes a dark (brown) iris pigmentation, how- ever, the heterozygous state rs12913832:GA includes a range of mixed variants. The predictive value of rs1800407 for the genetic phenotyping is highly significant (SE = 0.98), but has a low specificity (SP = 0.14), thus rs1800407, not being an effective classifier, can be used as an auxiliary in the eye color predictive model. The analysis of a cumulative impact of the both poly- morphisms on the iris color variation shows their high prospects for the genetic phenotyping of the Belarusian population.

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