Keragaman genetik gen hormon pertumbuhan (GH) dan hubungannya dengan kualitas karkas pada sapi aceh

Abstract

This study was conducted in order to identify polymorphism of growth hormone gene and to characterize nucleotide changes and its position in the DNA sequence of the exon five in the bovine growth hormone gene. In addition, this study was done to determine the association of GH/AluI polymorphism with carcass quality and to describe D-Loop of mtDNA and microsatellite alleles in Aceh cattle. A total of 242 DNA genome samples were extracted from four Aceh cattle population, i.e., Banda Aceh (29), Aceh Besar (30), Indrapuri (129), and Saree (54), while for sample comparison was derived from the Gen Bank. The bGH gene was sequenced to identify new single nucleotide polymorphism (SNP). The sequence data were analyzed using BLAST and MEGA 4 software, and the PCR-RFLP was used to amplify 404 bp of GH gene. D-Loop sequences of mtDNA amplification were done by using specific primer with the PCR product of 980 bp, and the dnaSP program was used to build the NJ tree and to identify the haplotype. Three markers of BM1824, SPS115, and ILSTS028 were used for microsatellite DNA genotyping. The data of genotyping was analyzed using GeneMapper versi 4.0 software and Excel program. The result showed that one new SNP was found in the exon five of bGH gene, which located at position of 2.230 bp (C/T). Genotype frequencies of SNP in position 2.230 bp of Aceh cattle were 0.36; 0.14; and 0.50; for CC, TT, and CT respectively. On the contrary, the LL genotype was the only genotype which found in other Aceh cattle population. This finding indicated that there was not evidence of polymorphism of GH/AluI in Aceh cattle, and there was not correlation of GH/AluI gene with carcass quality of Aceh cattle. It could be affected by small number of sampling size. D-Loop mtDNA analyses showed that there was 27 haplotypes, and 28 Aceh cattle integrated into group of Buthan, China, India, and Zebu cattle with maternal origin of Bos indicus and one sample was from Bos taurus. These finding could be assumed that Aceh cattle has more genetic introgression of Bos indicus compared to that Bos taurus breeds. Microsatellite analyses showed that the average number of allele per locus was 7.6. The genotype of Indrapuri population was higher than those of Banda Aceh and Saree population. Based on the microsatellite alleles analyses, the frequency of C alele locus of SPS115 and ILSTS028 was higher in Indrapuri population. Nevertheless, these locus could be uses for further study to get more information about polymorphism in Indrapuri population. However, this study suggests that GH gene could be possible used as genetic marker.