cysteinyldopa and Albinism--Oculocutaneous

The contents of eumelanin and pheomelanin in the scalp hairs of 4 Japanese patients with total albinism (3 tyrosinase-positive and one negative) and 100 healthy Japanese were measured by the melanin microquantitation method of Ito and Fujita. The urinary 5-S-Cysteinyldopa (5-S-CD) and 5-Hydroxy-6-Methoxyindole-2-Carboxylic acid (5H6MI2C) contents in the 4 albino subjects were also determined. Our findings included that (1) Regardless of ge, black hairs of all the healthy subjects contained phemelanin at a level of about 5% of the total melanin contents. The hair color of the 3 tyrosinase-positive subjects was pale-yellow, and their hairs contained only pheomelanin. The hair color of the one tyrosinase-negative subject was white, and neither eumalanin nor pheomelanin could be detected. (2) Urinary 5H6M12C, an indicator of eumelanin production in the body, could not be detected in either the tyrosinase-positive or tyrosinase-negative subjects, while the urinary 5-S-CD content of the tyrosinase-negative subject was much lower than that of the tyrosinase-positive subjects. These results suggested that the yellow hair color of patients with tyrosinase-positive albinism is attributable to the production of only pheomelanin and that the urinary 5-S-CD content does not necessarily reflect the ability to produce melanin.

Topics: Adolescent; Adult; Albinism, Oculocutaneous; Child; Child, Preschool; Cysteinyldopa; Female; Hair; Humans; Indoles; Japan; Male; Melanins; Middle Aged; Monophenol Monooxygenase; Reference Values