Population Genetic Structure of Three Cichlids in ‎Ilorin, North-Central Nigeria

Abstract


 
 
 
 Cichlids are among the economically important which serve as a source of food for people ‎around the world. A deep understanding of the population structure and genetic diversity of ‎cichlids are vital for initiation of conservation policies and sustainable aquaculture. There is ‎paucity of information on the patterns of genetic variations among and within cichlids in ‎North-central Nigeria. This study, therefore, investigated population genetic structure of ‎Coptodon zillii, Oreochromis niloticus, and Hemichromis fasciatus collected from different ‎freshwater bodies in North-central Nigeria. Genomic DNA was extracted, and five highly ‎polymorphic RAPD primers were used for RAPD-PCR amplification and genotyping of the ‎fish. Genetic polymorphism within and between the three tilapia species were examined. ‎Percentages of polymorphism loci, pairwise population matrix, analysis of molecular variance ‎‎(AMOVA), and genetic distances of cichlid populations were determined using standard ‎methods, and dendrograms were constructed using an un-weighted pair group method of ‎arithmetic mean (UPGMA). Overall, percentages of estimated molecular variance within and ‎among C. zillii, H. fasciatus and O. niloticus populations were 5% and 95%; 4% and 96% and ‎‎13% and 87%, respectively. Our results suggest that the three cichlids have close evolutionary ‎relationship and there were no distinct genetic differences on the basis on sampling locations. ‎C. zillii and H. fasciatus are more genetically closer than O. niloticus. This study concludes that ‎RAPD is useful in studying the population genetic structure of cichlids. This study therefore ‎recommends conservation of genetic pool of cichlid species through proper maintenance and ‎restoration of polluted habitat to guarantee sustainable fishery production. However, markers ‎such as microsatellite DNA can be assayed in further studies for better results‎.
 
 
 

Genetic Similarity Levels in Nile Tilapia of Some Nigerian Water Bodies Using SSR Markers

“…These data supported the view that the very high similarity between tilapia leads to a high probability of hybridization between them, based on the genetic distance between strains we may deduce that there are varying levels of genetic variability among O. niloticus in Nigeria water bodies under study. Genetic variability among O. niloticus observed in this study was consistent with previous studies of this species using both mtDNA and nuclear markers 17,22,33,35,[40][41][42] .…”