Genetic Diversity Assessment of Three Populations of Chrysichthys nigrodigitatus (Lacepede, 1803) in Southwestern Nigeria Using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE)

Chrysichthys nigrodigitatus, a highly valued food fish, was examined for its genetic diversity across three different water bodies (Epe lagoon, Asejire reservoir, and Igbokoda river) in southwestern Nigeria, using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis. Samples from each population were analyzed following standard protocols. The protein bands obtained as outputs of the SDS-PAGE analysis were scored as present (1) or absent (0) to create a binary matrix which was used to determine the following indices of genetic diversity: number of alleles, percentage polymorphism, heterozygosity, and Shannon’s information index using GenAlEx v. 6.5. A dendrogram was constructed by the unweighted pair group method with arithmetic average (UPGMA) using MEGA software. Results revealed a low level of genetic diversity in the three populations; however, genetic diversity was relatively higher in the Asejire reservoir population compared to the Igbokoda river and Epe lagoon. The UPGMA dendrogram indicated that the Asejire reservoir and Epe lagoon populations are genetically closer, forming a single cluster, while the Igbokoda river population is distinct from them, suggesting that this population is genetically different. The study concluded that the low genetic diversity observed in the three populations of C. nigrodigitatus indicates an urgent need for monitoring and conservation efforts to ensure their long-term survival and sustainable yields.