Genetic characterization of wild and domesticated common carp ( Cyprinus carpio L.) populations from Uzbekistan

Abstract

One domesticated and five wild common carp populations from Uzbekistan have been genetically characterized by examining variability at 22 allozyme loci. The observed level of polymorphism was high (1.4–1.7 alleles per locus, 26.3–42.1% polymorphic loci and expected heterozygosities from 0.098 to 0.146) and similar to that previously found in German or East Asian populations. The Uzbek wild populations, with the exception of the paired populations of Lake Arnasaiskie and Syr-Darya channels, were genetically very similar to each other as reflected by nonsignificant F ST values and clustering into one distinct group with high bootstrap support. In contrast, the differentiation between all Uzbek wild and the Uzbek domesticated carp was highly significant as well as the differentiation between Uzbek and German, Uzbek and East Asian, and German and East Asian populations. The Uzbek domesticated carp clustering with River Amur wild carp could be explained by their proposed crossing with Ropsha carp (a derivative of Amur wild carp), which could have taken place in their breeding history. Allelic distribution at some loci is consistent with introgressive hybridization between Uzbek domesticated carp and Syr-Darya channels wild carp. Considering that wild common carp has already disappeared, is endangered or has mixed with domesticated carp in many other parts of its natural distribution area, it is very important to conserve the wild populations in Uzbekistan in order to maintain the genetic diversity of the species.