Genetic variation of Mehraban sheep using two intersimple sequence repeat (ISSR) markers

Abstract

Genetic diversity within Mehraban sheep populations, as one of the main breeds of Iranian sheep, was studied using (AG)₉C and (GA)₉C as two inter-simple sequence repeat (ISSR) markers. Blood samples were collected from 210 animals in 6 flocks, 35 heads each, in different parts of Hamedan province. In the polymerase chain reaction (PCR) products, (AG)₉C and (GA)₉C primers amplified 28 and 36 fragments, respectively, which ranged from 100 to more than 3100 bp. Percentages of polymorphic bands in the different populations ranged from 69 to 77%. In the pooled population, all inter-simple sequence repeat (ISSR) fragments were polymorphic. Shannon and Nei gene diversity indices were 0.2256 and 0.1258, respectively, which indicated low genetic diversity of Mehraban sheep. The population studied was at Hardy-Weinberg equilibrium for most of the ISSR-loci. Analysis of molecular variance (AMOVA) partitioned the ISSR variation into inter and intra population components, where inter-populations and intra-populations accounted for 9 and 91% of the total variation, respectively. The results of this study showed that the Mehraban sheep is a pure native breed that has a low genetic diversity between subpopulations and could be noticed for its potentials in response to selection or crossing with other breeds.

Key words: Inter-simple sequence repeat (ISSR) markers, Mehraban sheep, genetic diversity.