Polymorphism leu/val of Growth Hormone Gene Identified from Limousin Cross Local Cattle in Indonesia

Abstract

This study attempted to identify Leu/Val polymorphism of growth hormone gene in Limousin cross local cattle. The DNA samples were collected from Madura cattle (65), Limousin-Madura cattle (81), Ongole Crossbred cattle (PO, 52), and Limousin-PO cattle (56), also Limousin bull semen (6). A 211 bp DNA fragment of growth hormone gene spanning from the forth intron (49 bp) to five exon (162 bp) was amplified using PCR method and digested with AluI restriction enzyme to identified polymorphism at this locus. Two genotypes LL and LV were observed in PO (96.15%LL, 3.85%LV), Limousin-Madura (81.46%LL, 18.52%LV), Limousin-PO cattle (78.57%LL, 21.43%LV), and Limousin (66.67%LL, 33.33%LV). Madura cattles were found monomorphic for this locus producing only one genotype LL (100%). The results of this research show that the increasing number of genotype leu/val in Limousin cross local cattle is about 17.58% and 18.52% for Limousin-PO cattle and Limousin-Madura, respectively, compared to the local cattle (PO and Madura cattle). The allelic frequencies are statistically similar as revealed by Chi-Square test. This research concludes that the polymorphic leu/val of growth hormone gene occurs in Limousine-cross local cattle whereas monomorphic leu/leu of growth hormone gene is found in Madura cattle. Thus, the finding of this research would be useful as a control for genetic equilibrium in Madura cattle population and to protect uncontrolled crossbreeding.