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bioRxiv · 10.1101/2025.01.20.633999

A Recessive oca2 Mutation Underlies Albinism in Xiphophorus fish

Xing, Y.·Boswell, W.·Parker, J.·Du, K.·Schartl, M.·Lu, Y.
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Abstract

Oculocutaneous albinism (OCA) is a group of genetic disorders characterized by impaired melanin production, leading to reduced pigmentation in the skin, hair, and eyes. Xiphophorus, a genus of small freshwater fish, has been a pivotal model organism in pigmentation disorder research, providing key findings in the genetic pathways governing physiological and pathological pigment cell biology. Leveraging the well-established research framework provided by Xiphophorus, we have identified a spontaneously occurring albinism phenotype in swordtail fish Xiphophorus hellerii. Genetic mapping of albino fish showed that albinism is associated with a recessive mutation in the oca2 gene. This discovery provides a novel opportunity to explore functions of oca2 gene in pigment cell differentiation, pigment synthesis, melanosome assembly and transportation function and amelanotic melanoma development.

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Xing, Y., Boswell, W., Parker, J., Du, K., Schartl, M., Lu, Y.. 2025-01-23. A Recessive oca2 Mutation Underlies Albinism in Xiphophorus fish. https://doi.org/10.1101/2025.01.20.633999

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