Early sexing of Tilapia nilotica (Oreochromis niloticus) by using short sequence repeats (SSRs) molecular markers

Abstract

Aquaculture is a promising of the Nile tilapia ( Oreochromis niloticus , L.), an important issue in Egypt. The present study's objective was to use short sequence repeats markers (SSRs) in the early sexing of O. niloticus . Molecular markers identification in fish includes SSRs markers that were very useful for investigating sex-determination system, sex-related genes, and sex chromosomes. The fin-clip tissue of examined fish was used for DNA extraction and the amplification of SSRs and sex determination; twenty primer pairs were tested. The results showed that, from the tested 21 primers of SSRs markers, four primers had significant differences between males and females. It was observed that females were homozygous, and males may be heterozygous or homozygous for the alternative bands. The females were homozygous, males were heterozygous for two SSRs markers, the females were homozygous, and males were homozygous for the alternative alleles for the other two markers. In conclusion, the results of the present study and the previous ones confirm the possibility of using short sequence repeats markers (SSRs) in the sex determination of fish species, including Nile tilapia ( Oreochromis niloticus , L.). SSRs markers could be used in the early sexing detection of the Nile tilapia breeding programs and for producing supermale YY without needing progeny test.