Genetic Variants of β-Lactoglobulin Gene in Garole, Malpura, Patanwadi and Their Crossbred Sheep

Several milk protein polymorphisms have been considered as potential tool for selection of dairy animals. β-lactoglobulin (β-LG) is one of the major whey proteins in ruminant milk. A study was aimed to identify the genetic variants of β-LG gene in Garole (G), Malpura (M), Patanwadi (P) and their crosses i.e. GM, GMM, GMMxP (A), PxGMM (B) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Two genetic variants and three genotypes were found in all the breeds and crossbreds. Overall frequency of alleles A and B in the breeds and crossbreds were 0.55 and 0.45, respectively. Allele ‘A was more frequent than allele ‘B ’in all the breeds and crossbreds except Patanwadi and GM cross. The GMM crossbred had the highest frequency of ‘A ’allele (0.64) while Patanwadi and GM crossbred had the lowest (0.40). There was predominance of ‘AB ’genotype in these breeds and crossbreds. BB genotype predominated in Patanwadi and GM crossbred with genotypic frequencies of 0.45 and 0.49, respectively. All the genetic groups were in Hardy-Weinberg equilibrium except Malpura, Patanwadi and GM crosses. It can be concluded that variation exist in the Indian sheep breeds/strains at studied locus of β lactogloublin and these variation can be utilized in future to study the effects of different variants on the milk production and quality traits.