Genotyping Analysis of rs1799989 Single Nucleotide Polymorphism in TYR Gene Region in the Population of Isfahan, Iran


1 M.Sc. in Genetics, Department of Biology, School of Science, University of Isfahan, Isfahan, Iran

2 Professor, Department of Biology, School of Science, University of Isfahan, Isfahan, Iran


Background & Aims: Tyrosinase is the most important enzyme in the production of pigments of the skin, eyes, and hair follicles. The enzyme is encoded by tyrosinase gene (TYR) or oculocutaneous albinism type 1A (OCA1A). Mutations in TYR gene result in pigmentation disorders such as albinism in humans. In view of the large number of mutations reported in this gene, the aim of this study was to identify and introduce polymorphic markers located in the TYR gene region in the Iranian population. Methods: In the present study, using bioinformatics investigations for single nucleotide polymorphisms (SNP) markers in TYR gene region, rs1799989 marker was selected and genotyped through tetra primer amplification refractory mutation system-polymerase chain reaction (ARMSPCR) method. The allele frequency and heterozygosity degree of this marker was analyzed in the population of Isfahan, Iran. Results: The heterozigosity of the rs1799989 marker (75.9%) in the population of Isfahan was high. The frequency of allele C and allele A was 0.576 and 0.420, respectively. Comparison of this finding to those of other populations showed that the most similarity existed with African populations. Conclusion: In view of the high degree of heterozygosity, rs1799989 marker can be introduced as an informative marker for linkage analysis and identification of TYR gene mutations carriers in the Iranian population.


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