Genetic characterization of Gaddi goat breed of Western Himalayas using microsatellite markers

AIM: In the present study, genetic characterization of Gaddi goat breed, a native to north temperate western Himalayan region of India, was carried out for the purpose of breed characterization and assessing existing intra-population genetic diversity. MATERIALS AND METHODS: Totally, 75 blood samples procured at random from genetically unrelated animals of two sexes and different age groups and true to breed type were collected from different locations in the breeding tract of these goats in Himachal Pradesh, of which only 51 samples with desired quantity and quality were subjected to further processing for DNA isolation. The multi-locus genotype data were generated on 51 Gaddi goats sampled across different regions of the breeding tract in Himachal Pradesh using 15 FAO recommended goat specific microsatellite markers, which gave amplification and observed and effective number of alleles, gene frequency, observed and expected heterozygosity were estimated through PopGene software (1.3.1). RESULTS: A total of 135 distinct alleles were observed with mean observed and effective number of alleles as 9.0000±0.82 and 6.5874±0.56 respectively across all 15 studied loci. The maximum (15) alleles were contributed by loci DRBP1 and P19/DYA and the least (5) by SRCRSP5. The mean heterozygosity was observed to be 0.8347±0.01 ranging from 0.7584 (SRCRSP5) to 0.9156 (P19-DYA) across all loci. The mean observed (H(O)) and expected (H(E)) heterozygosities across all loci were 0.7484±0.02 and 0.8431±0.01 respectively. The polymorphism information content (PIC) value ranged from 0.7148 (SRCPS5) to 0.909 (P19-DYA) with mean PIC of 0.8105±0.01 in the present study. The average heterozygosity was observed to be 0.8347±0.01 ranging from 0.7584 (SRCRSP5) to 0.9156 P19 (DYA) across all loci. CONCLUSION: Microsatellite analysis revealed high level of polymorphism across studied microsatellite markers and informativeness of the markers for genetic diversity analysis studies in Gaddi goats. This high level of polymorphism can be utilized to plan future association studies to exploit the uniqueness and adaptability of indigenous Gaddi goat breed of Western Himalayas. Most studied microsatellite markers had desired neutrality, thus proving to be good candidates for genetic characterization and diversity analysis in Gaddi breed of goats also.