Molecular Characterization of the Growth Hormone Gene in Riverine Buffaloes

Growth hormone, a protein hormone, has a remarkable role in growth, reproduction and milk production. The present investigation was aimed at studying the genetic variation in growth hormone gene locus 4th exon, 4th intron and 5th exon in Murrah buffalo bulls by PCR-RFLP. The growth hormone gene was amplifi ed by PCR using oligonucleotide primers standardized for Bos taurus species. A 428 bp fragment of growth hormone gene spanning over 4th exon, 4th intron and 5th exon was amplifi ed and digested with Alu I restriction enzyme using a cattle specifi c primer. The sizes of the amplifi cation products were similar in cattle and buffalo. Growth hormone gene in buffalo reveals monomorphism since no variation was found. The result indicates strong conservation of DNA sequence between cattle and buffalo. Nucleotide sequence variations and amino acid variation were observed at growth hormone gene between Bubalus bubalis and Bos taurus species reveals 97.1% nucleotide identity 12 nucleotide substitutions, but a single amino acid change. A phylogenetic tree constructed for buffalo with other species revealed buffalo were closer to cattle and yak compared to other species. The growth, milk production, seminal and sexual behavioral parameters could not be associated with buffalo growth hormone genotypes due to their monomorphic haplotype.