Genetic characterization and assessment of demographic bottleneck in Caspian horse population.

The aim of this study was to evaluate genetic characterization of the Caspian horse population using microsatellite markers. This study determined the efficiency of microsatellite markers for conservation plans and breeding strategies in Caspian horse population. For this purpose, 120 Caspian horse samples including 95 adults and 25 foals were genotyped by using seventeen microsatellite markers recommended by ISAG. The number of allele per locus varied from 5 (HMS01 and HTG07) to 9 (HTG10) with an average value of 7.41. The observed heterozygosity and the expected heterozygosity ranged 0.505-0.831 (mean 0.684), from 0.615-0.835 (mean 0.748) respectively. PIC value ranged from 0.716 (HMS01) to 0.834 (AHT04) with average 0.787. The total exclusion probability of the 17 microsatellite loci was 0.9999. Low values of Wright's fixation index, Fis (0.084) indicated low levels of inbreeding. A significant heterozygote excess on the basis of different models suggested that Caspian horse population has decreased to low numbers in the past, but a bottleneck event is still scrutable, and its number has recently increased is not in mutation drift equilibrium. The present study contributes to our knowledge of the genetic diversity of the Caspian horse population and helps to define its genetic conservation strategies.