title: 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.
  
  
  CONCLUSIONS
  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: Brazilian Agricultural Research Corporation, Embrapa, Pelotas, Rio Grande do Sul 96.001-970, Brazil.
authors: Maria Cecília Florisbal
authors: MC
authors: Damé
authors: Gildenor Medeiros
authors: GM
authors: Xavier
authors: José Paes
authors: JP
authors: Oliveira-Filho
authors: Alexandre Secorun
authors: AS
authors: Borges
authors: Henrique Nunes
authors: HN
authors: Oliveira
authors: Franklin
authors: F
authors: Riet-Correa
authors: Ana Lucia
authors: AL
authors: Schild
mesh_terms: D016115:Albinism, Oculocutaneous / Q000235:genetics*; D000818:Animals; D002020:Buffaloes / Q000235:genetics*; D018389:Codon, Nonsense; D018388:Codon, Terminator; D014442:Monophenol Monooxygenase / Q000235:genetics*; D010641:Phenotype; D010858:Pigmentation / Q000235:genetics; D020641:Polymorphism, Single Nucleotide
chemical_list: D018389:Codon, Nonsense; D018388:Codon, Terminator; D014442:Monophenol Monooxygenase