Analysis of bovine growth hormone gene polymorphism of local and Holstein cattle breeds in Kerman province of Iran using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP)

Bovine growth hormone (bGH) gene is a part of the multiple gene family that contains prolactin and placental lactogens. Also, variations in introns have potential usefulness as genetic markers and could help in the genetic improvement of populations. Genomic DNA was isolated from blood samples of two local herds (53 animals) and two Holstein herds (50 animals). Genomic DNA samples were genotyped for the GHI-AluI polymorphism by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). A 211 bp (bGH) gene exon 5 segment was amplified by PCR using bovine specific primers. RFLPs in this segment were studied using AluI restriction enzyme. The frequencies of V and L alleles in the local and Holstein herds were 0.2 and 0.65, respectively. For both herds, significant difference from the Hardy-Weinberg equilibrium was observed.Key words: Growth hormone, polymorphism, polymerase chain reaction restriction fragment length polymorphism, local herds, Holstein herds