RESUMO

The insulin-like growth factor I (IGF-1) gene plays important roles in the growth and body composition of animals. Serum IGF1 concentration has been associated with growth traits in many livestock species. We found a polymorphism of cattle IGF1-TasI locus and analyzed the distribution of alleles in three cattle breeds, including Qinchuan, Nanyang, and Chinese Holstein. PCR-RFLP analysis showed that allele A was the dominant allele. The frequencies of allele A varied from 0.84 to 0.97. Distributions of genotypic and allelic frequencies were significantly different among breeds. Polymorphism of the IGF1 gene was significantly affecting hucklebone width at 6 months in the Nanyang breed and protein and fat yield of the third lactation in Chinese Holstein cattle. Individuals with allele C had a significantly higher performance in production traits.

Assuntos

Regiões 5' não Traduzidas/genética , Bovinos/genética , Fator de Crescimento Insulin-Like I/genética , Polimorfismo de Nucleotídeo Único , Alelos , Animais , Animais Recém-Nascidos , Composição Corporal/genética , Pesos e Medidas Corporais , Bovinos/classificação , Bovinos/crescimento & desenvolvimento , China , Feminino , Frequência do Gene , Estudos de Associação Genética/métodos , Genótipo , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Especificidade da Espécie , Fatores de Tempo