Genetic diversity of Najdi sheep based on microsatellite analysis
The prime objective of this research was to measure the genetic polymorphism of main sheep breed of Saudi Arabia, Najdi. Randomly selected 49 blood samples were used to extract the DNA followed by polymerase chain reaction (PCR), using 19 microsatellite markers, which were used to investigate the genetic differentiation. Altogether, 173 alleles were identified ranging from 2 to 14, with the mean observed number alleles per locus of 9.11 ± 3.54. Apart from that, eight loci showed breed specific alleles which is critical in terms of conservation. The observed heterozygosity, expected heterozygosity, polymorphic information content and Shannon index, were 0.67 ± 0.19, 0.75 ± 0.14, 0.71 ± 0.16 and 1.69 ± 0.51, respectively. Therefore, considerable amount of genetic polymorphism has been shown by Najdi. Inbreeding coefficient of 0.13 exhibited moderate level of inbreeding prevailing, which may be partly due to the Wahlund effect (sub-population structure) at level of sampling. Nine out of the 19 loci encountered significant departure from Hardy Weinberg Equilibrium (p < 0.05). Based on the bottleneck analysis, there was no bottleneck effect in Najdi. This paper reports a comprehensive study on genetic diversity of Najdi, hence, it would be used for further advancement of this breed towards utilizing them sustainably.
Keywords: Polymerase chain reaction (PCR), diversity, microsatellites, sheep, inbreeding