Thelansis

  Oculocutaneous albinism (OCA) encompasses a diverse set of autosomal recessive disorders affecting melanin production, resulting in congenital skin, hair, and eye hypopigmentation. Standard features include reduced visual acuity, photophobia, iris transillumination, foveal hypoplasia, nystagmus, and abnormal nerve fiber decussation at the optic chiasm. Ocular albinism (OA) shares these ocular traits, including increased nerve fiber decussation, with OCA. OA patients typically have fairer complexions than their unaffected siblings and exhibit macro melanosomes in the skin, although skin hypopigmentation is generally less pronounced than in OCA. OCA is classified into several types (OCA1, OCA2, OCA3, OCA4, OCA5, OCA6, and OCA7) based on the mutated gene. Recent hypotheses suggest that the clinical presentation of OCA depends on the patient's pigmentation threshold. Darker complexion individuals like Africans may require two mutations to completely inhibit pigmentation. In compari...