A nonsense mutation in the tyrosinase gene causes albinism in water buffalo

作者：Flori**al Dame Maria Cecilia; Xavier Gildenor Medeiros; Oliveira Filho Jose Paes; Borges Alexandre Secorun^*; Oliveira Henrique Nunes; Riet Correa Franklin; Schild Ana Lucia

来源：BMC Genetics, 2012, 13: 62.

DOI：10.1186/1471-2156-13-62

• Albinism
• Buffalo
• Nonsense mutation
• Stop codon
• Tyrosinase

Background: Oculocutaneous albinism (OCA) is an autosomal recessive hereditary pigmentation disorder affecting humans and several other animal species. Oculocutaneous albinism was studied in a herd of Murrah buffalo to determine the clinical presentation and genetic basis of albinism in this species.
Results: Clinical examinations and pedigree analysis were performed in an affected herd, and wild-type and OCA tyrosinase mRNA sequences were obtained. The main clinical findings were photophobia and a lack of pigmentation of the hair, skin, horns, hooves, mucosa, and iris. The results of segregation analysis suggest that this disease is acquired through recessive inheritance. In the OCA buffalo, a single-base substitution was detected at nucleotide 1,431 (G to A), which leads to the conversion of tryptophan into a stop codon at residue 477.
Conclusion: This premature stop codon produces an inactive protein, which is responsible for the OCA buffalo phenotype. These findings will be useful for future studies of albinism in buffalo and as a possible model to study diseases caused by a premature stop codon.

• 出版日期2012-7-20