Polymorphism in the 5ꞌ-UTR of the insulin-like growth factor I gene associated with production traits in Chinese cattle
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.