Polymorphism and phylogenetic analysis of FecB and FecG genes in native sheep of Meghalaya, India.

The present study was conducted to identify the polymorphism of two major fecundity genes, viz. FecB and FecG, in indigenous sheep of Meghalaya and to assess phylogenetic relationship with 15 breeds of sheep and to estimate the sequence distances between them. Blood samples were collected from 50 adult ewes and PCR-RFLP was performed to detect the polymorphism of these genes. Further digestion of FecB and FecG was done with restriction enzymes AvaII and DdeI, respectively. In the case of FecB gene, two genotypes, viz. AA and AB, were identified where AA genotype yielded one fragment (190 bp) and AB genotype yielded two fragments (160 and 30 bp). The frequencies of A and B alleles were calculated as 0.64 and 0.36 and those of AA and AB genotypes as 0.280 and 0.720 respectively, whereas FecG gene was found to be monomorphic, with only a single genotype designated as AB genotype. Measure of relatedness among Indian and exotic sheep in terms of both the fecundity genes threw light on the evolutionary origin of different sheep breeds.

Allelic variability of estrogen receptor (ESR) gene and its effect on litter traits of Doom pigs.

The present study was conducted to identify the polymorphism of estrogen receptor (ESR) gene and its biological association with litter traits (litter size at birth, litter size at weaning, litter weight at birth and litter weight at weaning) of Doom pigs native to Assam. A total of 50 adult pigs (12 males and 38 females) chosen randomly from three different herds (Herd I, Herd II, and Herd III) were utilized in the present study. Detection of polymorphism of ESR gene was done by means of PCR-RFLP method. The amplified PCR product was digested with Pvu II restriction enzyme. PCR-RFLP analysis of ESR gene revealed polymorphic banding pattern. Two genotypes viz. AA and AB were identified. AA genotype yielded one fragment (120 bp) and AB genotype yielded three fragments (120, 65, and 55 bp). BB genotype was not found in the population under study. The frequencies of A and B alleles were found to be 0.650 and 0.350, respectively, and the genotypic frequencies of ESR gene were found to be 0.300 and 0.700 for AA and AB genotypes, respectively. There was no significant (P > 0.05) effect of ESR genotype on litter traits and the population under study was not in Hardy-Weinberg Equilibrium for ESR gene. Clustal W Multiple alignment of partial sequence of ESR gene revealed single nucleotide changes at 33, 65, 70, 83, and 92nd nucleotide positions. The presence of Pvu II polymorphism and identification of single nucleotide variation of ESR gene opens interesting prospects for improvement of litter traits in Doom pig through selective breeding program, especially based on marker-assisted selection.