Gene study within the 5' flanking regions of growth hormone gene of first exon in <i>Bos indicus</i>

Abstract

Growth hormone (GH) is a main regulatory protein secreted by pituitary gland and placenta, involved in most anabolic processes in mammals. Expression of more than one gene for GH has been reported, indicating polymorphism at gene and protein level; apart from this, silent mutations has also been reported, relating to the level of expression of GH gene. The aim of this study is to identify silent mutations within the 5' flanking regions of GH2 gene of the first exon in Bos indicus. DNA was isolated
from the blood of freshly slaughtered animal and a set of primer was used for gene amplification, binding at 5' flanking region of GH gene at chromosome 19. DNA was amplified and the resultant product of about 453 bp was sequenced. The results showed that there were 9 changes including 8 replacements and one addition, for GH 2.3 allele, as compared to Bos taurus Genome (Btau_4.0 ) and two earlier reported alleles 2.1 and 2.2 for GH2 gene in B indicus. As this region is related to higher milk production, growth regulation, carcass and immune response traits in livestock, these changes could be used as a genetic marker. The reported sequence has been deposited to the European Molecular Biology Laboratory (EMBL) with the Accession Number FN666263.

Key words: Bos indicus, growth hormone gene, silent mutation, growth hormone (GH) gene, allele.