Effect of TGF-β3 Gene Polymorphism on some Blood Parameters in Local Chickens

Abstract

Iraqi native chickens are noted for their ability to tolerate a wide variety of infectious diseases as well as high temperatures. The basic physiological routes, including proliferation, differentiation, metabolism, and apoptosis, are intricately regulated by a dense signaling network that is elicited by cytokines, growth factors or polypeptide hormones. Among those polypeptide/hormone-induced signals, the transforming growth factor-beta (TGF-β) family is chiefly important. However, the present study attempts to identify associations between physiological parameters and polymorphism of TGF-β3 gene in local chicken. Seventy five female birds were used in this study. A single nucleotide polymorphism was identified at 9361 position in the exons 3-6 region of TGF-β3 by using PCR-RFLP and DNA sequencing technique. The restriction enzyme BsrI has been used to detect the target region (1078 bp) in the TGF-β3 gene. The genotypic frequencies were 57.33, 24 and 18.67% for AA and CA and CC genotypes respectively. While, the allele frequency of genes A and C were 0.69 and 0.31%, respectively. Generally, during the last period of rearing we demonstrated a more positive correlation (p>0.05) among blood values such as RBC, Hb, WBC, H/L ratio, total protein and gamma globulin with CA genotype. In conclusion, the TGF-β3 gene could be used as a candidate gene of QTL for improving physiological traits in local chickens.