A study of DNA sequence variations in melanocortin-1-receptors or MC1R genes found many variants of amino acid found in people who were red-haired but rarely found in the non-red people. Researchers have identified 3 common amino-acid-polymorphisms associated commonly with red haired people viz., R160W, R151C, & D294H. The abbreviated names mean common amino acid types were found in positions 160 151, & 294 in proteins are arginine (R), cysteine (C), arginine & aspartic acid (D), while amino acids histidine (H) & tryptophan (W), were found in the redheads (Catherine A Guenther, 2016).
Many rare polymorphisms of amino acid are there in MC1R genes, some may be linked to red hair. Surveys of genetic variations in genomes …show more content…
Davenport & Davenport (1909) had reported many examples of 2 brown-hair parents with red-hair offspring’s which could suggest it is because of recessive alleles, but Neel (1943) established 13 in 114 offspring’s of 2 red-hair parents had non-red hair. Reed (1952) reviewed various hypotheses which have been proposed. Valverde et al. (1995) made a survey of DNA sequence variations. Beaumont and others in 2007 surveyed the genetic variations of the genome in many …show more content…
The IRF4 gene was known to play an important role in determining hair color, but it is also related to gray hair. It has been possible because we have analyzed a very diverse group of people such as Latin Americans, which had not been done at this scale previously," adds the expert. The IRF4 gene is responsible for regulating the production and storage of melanin, the pigment that determines the color of hair, skin and eyes. The gray hair is precisely caused by the absence of melanin in the hair (Jablonski,