Development and characterization of 49 novel microsatellite markers in the African catfish, Clarias gariepinus (Burchell, 1822).

The African catfish or sharp tooth catfish (Clarias gariepinus) is one of the important species (due to its high environmental tolerance and easily controllable breeding habits) that can significantly contribute to reducing hunger in many countries. It is farmed in numerous African, Asian, and European countries. Moreover, during the last decades its production has grown significantly worldwide. Currently, following the carp, this species is produced in the second largest volume in Hungary. Despite its economic importance, the stocks have been maintained without genetic control or guided breeding. Molecular genetic data on bred populations or strains are very limited. In order to investigate the genetic structure of the stocks, 49 new microsatellite markers were characterized and tested on 32 individuals from a Hungarian farmed stock. All these markers were polymorph. The number of alleles per locus ranged from 2 to 11. The observed and expected overall heterozygosities were between 0.519 and 0.544 respectively and the overall inbreeding coefficient (Fis: 0.063) does not reveal the presence of inbreeding. However, 63% of the markers showed significant deviations from HWE. The results suggest that the maintenance of genetic variation within the stock require high attention in closed bred populations. These new markers provide a useful tool for population and conservation genetics of natural and bred African catfish populations.