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Melanin is a natural pigment found in various tissues throughout the body, most notably in the skin, hair, and eyes. Melanin is synthesized in the epidermis by specialized pigment-producing cells called melanocytes through a biochemical pathway that begins with the amino acid tyrosine. Although melanin's primary function is to protect cells from the damaging effects of UV radiation, it also plays essential roles in skin pigmentation, eye and hair color, evolutionary adaptation to sunlight, and aspects of cutaneous immune function. Disruptions in melanin production can lead to conditions such as albinism, characterized by little or no pigment in the skin, hair, and eyes. Oculocutaneous albinism type 1—the most common form—results from mutations in tyrosinase, a copper-dependent enzyme that is crucial for melanin synthesis. Phenylketonuria is another condition that affects pigmentation, a metabolic disorder characterized by elevated levels of phenylalanine due to a deficiency in phenylalanine hydroxylase. High phenylalanine levels competitively inhibit tyrosinase, thereby interfering with the conversion of tyrosine into melanin. As a result, individuals with phenylketonuria often exhibit fair skin, light hair, and blue eyes due to impaired melanin production.[1][2][3]