Albinism in humans Albinism in humans Albinism is a congenital disorder characterized in humans by the complete or partial absence of pigment in the skin, hair and eyes. Albinism is associated with a number of vision defects, such as photophobia, nystagmus, and amblyopia. Lack of skin pigmentation makes for more susceptibility to sunburn and skin cancers. In rare cases such as Chédiak–Higashi syndrome, albinism may be associated with deficiencies in the transportation of melanin granules. This also affects essential granules present in immune cells leading to increased susceptibility to infection. Albinism results from inheritance of recessive gene alleles and is known to affect
Neoteny in humans Australia, said that he agrees that neoteny in humans may have become "accelerated" through "two-way sexual selection" whereby females have been choosing smart males as mates and males have been choosing smart females as mates. Neoteny has been important to human evolution, because it has increased the maturation period and the size of the human brain. Two to three million years ago, there was an "incomplete segmental duplication of [the] ancestral SRGAP2" gene in the ancestors of humans. This new gene, SRGAC2, slowed spine maturation and allowed for more neuronal migration. As a result, the dendrite spines increased in number