Albino

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Definition

noun, plural: albaninos

An organism with albinism, which is a condition characterized mainly by a lack of or an insufficient pigment (e.g. melanin) production


Supplement

An albino refers to an organism with albinism. In humans and animals, albinism is a congenital condition characterized by having a pale skin, light hair, pinkish eyes, and possibly visual abnormalities. In other animals (which most of them have multiple pigments), albinism is characterized by the partial or complete lack of pigment (thus, lack of coloration) in eyes, skin, hair, scales, fur, feathers, or cuticle. In plants, it is caused by the partial or complete loss of chlorophyll pigments. In humans and animals, albinism is caused by the lack of or inadequacy in melanin production. Melanin refers to a group of pigments produced from the oxidation of tyrosine, followed by polymerization. It is the one responsible for the color of skin, feathers, hair, fur, eyes, scales, etc. There are three basic types of melanin: (1) eumelanin, (2) pheomelanin, and (3) neuromelanin. The eumelanin is the most common type among the three. The eumelanin may be brown or black in colour. The pheomelanin is a pigment made up of benzothiazine units that is largely responsible for the red pigmentation whereas the neuromelanin is a dark pigment comprised of 5,6-dihydroxyindole monomers.

At the biomolecular level, the cause of this disorder is the absence of or defect in tyrosinase (tyrosine 3-monooxegenase). Tyrosinase is a copper-containing enzyme that is associated with melanin production. Without a functional tyrosinase, melanin cannot be produced sufficiently and therefore, this results in congenital characteristics such as pale skin, white hair, and red eyes.


Word origin: Latin albus (“white”)

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