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

Abstract

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.

• Authors: Maria Cecília Florisbal Damé, Gildenor Medeiros Xavier, José Paes Oliveira-Filho, Alexandre Secorun Borges, Henrique Nunes Oliveira, Franklin Riet-Correa, Ana Lucia Schild
• Journal: BMC genetics (BMC Genet) Vol. 13 Pg. 62 (Jul 20 2012) ISSN: 1471-2156 [Electronic] England
• PMID: 22817390 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Codon, Nonsense
• Codon, Terminator
• Monophenol Monooxygenase

Topics

• Albinism, Oculocutaneous (genetics)
• Animals
• Buffaloes (genetics)
• Codon, Nonsense
• Codon, Terminator
• Monophenol Monooxygenase (genetics)
• Phenotype
• Pigmentation (genetics)
• Polymorphism, Single Nucleotide