Polymorphism at growth hormone gene in Malabari goats investigated by PCR-RFLP

Abstract

The genetic polym~rphismw as investigated at the third intron of growth hormone (GH) gene in Malabari goats using the PCR-RFLP method. A random sample of 196 genetically unrelated Malabari does in second lactation belonging to 3 different populations were analysed. The successful amplification of the expected fragment indicated the suitability of bovine primers for goats and conservation of DAN sequence in related species. The digestian of the amplified product with MspI restriction enzyme revealed 2 alleles, viz. MspI (+) Mspl (-) with frequencies of 0.70 and 0.30 respectively. There was no significant variation in GHIMspl gene frequencies among the different populations, indicating the homogeneity of Malabari goats as a breed though they differ significantly with respect tomorphological and other phenotypic characters. The GHIMspI (+I-) genotype was associated with a significantly high (P<0.05) milk SNF percentage. Only (+I+) and (+I-) GHIMspI genotypes were encountered, whereas none of the animal was of the (-I-) genotype. It is possible that the Mspl (-) is closely linked to a lethal gene in Malabari goats. The population of the Malabari goats investigated in study was not under HWE, though it was a large random mating one with no known mutation, or migration. It is suggested that the selection process acting against the (-I-) genotype through reduced viability or early embryonic death may be a possible reason for the disagreement of the HWE in Malabari goats for this locus. Key words: Growth hormone gene, Linkage, Malabari goats, Mspl polymorphism,