<P> Red hair can originate from several changes on the MC1R - gene . If one of these changes is present on both chromosomes then the respective individual is likely to have red hair . This type of inheritance is described as an autosomal recessive mode of inheritance . Even if both parents do not have red hair themselves, both can be carriers for the gene and have a redheaded child . </P> <P> Genetic studies of dizygotic (fraternal) twins indicate that the MC1R gene is not solely responsible for the red hair phenotype; unidentified modifier genes exist, making variance in the MC1R gene necessary, but not always sufficient, for red hair production . </P> <P> The alleles Arg151Cys, Arg160Trp, Asp294His, and Arg142His on MC1R are shown to be recessives for the red hair phenotype . The gene HCL2 (also called RHC or RHA) on chromosome 4 may also be related to red hair . </P> <P> In species other than primates, red hair has different genetic origins and mechanisms . </P>

Where does red hair and blue eyes originate from