Microsatellite-based phylogeny of Indian domestic goats

Centre for cellular and Molecular biology, Uppal Road, Hyderabad-500007, India.
BMC Genetics (Impact Factor: 2.4). 02/2008; 9(1):11. DOI: 10.1186/1471-2156-9-11
Source: PubMed


The domestic goat is one of the important livestock species of India. In the present study we assess genetic diversity of Indian goats using 17 microsatellite markers. Breeds were sampled from their natural habitat, covering different agroclimatic zones.
The mean number of alleles per locus (NA) ranged from 8.1 in Barbari to 9.7 in Jakhrana goats. The mean expected heterozygosity (He) ranged from 0.739 in Barbari to 0.783 in Jakhrana goats. Deviations from Hardy-Weinberg Equilibrium (HWE) were statistically significant (P < 0.05) for 5 loci breed combinations. The DA measure of genetic distance between pairs of breeds indicated that the lowest distance was between Marwari and Sirohi (0.135). The highest distance was between Pashmina and Black Bengal. An analysis of molecular variance indicated that 6.59% of variance exists among the Indian goat breeds. Both a phylogenetic tree and Principal Component Analysis showed the distribution of breeds in two major clusters with respect to their geographic distribution.
Our study concludes that Indian goat populations can be classified into distinct genetic groups or breeds based on the microsatellites as well as mtDNA information.

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Available from: Pramod Rout
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    • "For instance, Zimbabwe chickens seem to form a unique genetic pool (Muchadeyi et al. 2007). Rout et al. (2008) showed that Indian goat breeds could be classified in two major genetic clusters. Zhang et al. (2007) studied 27 indigenous Chinese cattle breeds. "
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    • "Increasing F IT values suggest some measure of homozygosity and heterozygote deficit resulting from relatedness of individuals which may be a consequence of the emergent population structure of Nigerian goats, not previously uncovered by protein polymorphisms based on haemoglobin and transferrin. The presence of negative F IS values at loci ETH225, TGLA40, ILSTS5, SRCRSP10 and IDVGA7 suggests heterozygote deficiencies which have also been reported in other studies on goats (Barker et al., 1997; Luikart et al., 1999; Agha et al., 2008; Rout et al., 2008; Dixit et al., 2009). This heterozygote deficiency may arise due to population sub-structure from pooling together different populations (admixture) in the analysis (Cerda-Flores et al., 2002; Muema et al., 2009). "
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