DefinePK

Abstract

Coat color genetics has been studied in many mammalian species. However, in the dromedary camel, there are only few efforts reported three genes that associated with coat color (MC1R, ASIP and KIT). Saudi dromedaries vary in color from white, light brown, brown, dark brown and black. Tyrosinase (encoded by TYR gene) is a key enzyme responsible for converting tyrosine to melanin in the melanin pathway. TYR is known as the albino locus as it causes albinism in several mammalian species. TYR variants are also associated with diluted coat color phenotypes in rabbits and mice. Here, we investigated the possibility of TYR contribution in the dromedary coat color variations. Dromedary TYR exon 1 gene was studies in the dromedary and two SNPs were detected at position c.200 C>T associated with shoulder height in one study and suggested to be associated with coat color and c.523 T>C associated with black dromedaries. Here, we sequenced TYR all coding regions and identified 3 single nucleotide polymorphisms (SNPs) in exon 1, 2 and 3 respectively. Our finding shows that TYR c.200 C>T is significantly associated with light brown coat color phenotype in the dromedary (P<0.05) suggesting codominant inheritance. This variant substitutes a proline with leucine at position 67 (p.P67L). Two synonymous SNPs variants were discovered in exon 2 c.861 G>A and exon3 c.950 C>T. The finding will contribute to the generation of coat color genetic test in the species.