Single nucleotide polymorphism (SNP) in growth hormone gene of Jakhrana, a prominent milk goat breed in India

PCR-SSCP patterns on non-degenerative PAGE revealed 6 amplicons in caprine GH exon-4 and 3 alleles A(4), B-4 and C-4 were identified. In exon-5, six SSCP variants revealed three alleles A(5), B-5, and C-5. Out of 54 AA sites of GH-4 coding region, six codons were polymorphic. At codon-6, nucleotide substitution of CIA resulted in to genotypes 6(RR), 6(HH) and G/C into genotypes 6(pp), 6(RP). At codon-36, A/G nucleotide substitution resulted in to newer genotypes 36(GG) from that of 36(DD) in reference Genbank sample. At codon-54, C/T nucleotide substitution caused change of amino acid (AA) from arginine (R) to tryptophan (W) resulted into a new genotype of 54(ww) in comparison to 54(RR) of Genbank reference sample. In exon-5, out of 67 AA sites 8 codons were polymorphic, but the, codons 14 and 60 were preponderant. At codon-14, A/C substitution resulted into 3 genotypes 14(KK), 14(EE) and 14(KE) with frequency of 0.52, 0.38 and 0.10, respectively. At codon-60, G/C and G/A Substitutions resulted in to 3 genotypes 60(GG), 60(RR) and 60(GR) with frequencies of 0.48, 0.42 and 0.10, respectively. Synonymous mutations as compared to Genbank accession D00476.1 were present at codons 25, 31 and 62 in all the animals of Jakhrana goats. The high genetic variability in CH gene exon-4 and exon-5 may be useful in exploring their associations with milk and growth traits in goat for further genetic improvement. (C) 2008 Elsevier B.V. All rights reserved.