Tibetan is a valuable Himalayan sheep breed classified as endangered. Knowledge of the level and distribution of
genetic diversity in Tibetan sheep is important for designing conservation strategies for their sustainable survival
and to preserve their evolutionary potential. Thus, for the first time, genetic variability in the Tibetan population
was accessed with twenty five inter-simple sequence repeat markers. All the microsatellites were polymorphic
and a total of 148 alleles were detected across these loci. The observed number of alleles across all the loci was
more than the effective number of alleles and ranged from 3 (BM6506) to 11 (BM6526) with 5.920 ± 0.387
mean number of alleles per locus. The average observed heterozygosity was less than the expected heterozygosity.
The observed and expected heterozygosity values ranged from 0.150 (BM1314) to 0.9 (OarCP20) with an
overall mean of 0.473 ± 0.044 and from 0.329 (BM8125) to 0.885 (BM6526) with an overall mean 0.672 ±
0.030, respectively. The lower heterozygosity pointed towards diminished genetic diversity in the population.
Thirteen microsatellite loci exhibited significant (P b 0.05) departures from the Hardy–Weinberg proportions in
the population. The estimate of heterozygote deficiency varied from −0.443 (OarCP20) to 0.668 (OarFCB128)
with a mean positive value of 0.302 ± 0.057. A normal ‘L’ shaped distribution of mode-shift test and nonsignificant
heterozygote excess on the basis of different models suggested absence of recent bottleneck in the
existing Tibetan population. In view of the declining population of Tibetan sheep (less than 250) in the breeding
tract, need of the hour is immediate scientific management of the population so as to increase the population
hand in hand with retaining the founder alleles to the maximum possible extent.
© 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license