Genetic diversity of bonytongue fish Heterotis niloticus (Cuvier, 1829) in Cameroon, Central Africa

Abstract

The African bonytongue (Heterotis niloticus) fish is the only species of the Osteoglossidae family in Africa. The characterization of this fish was carried out from January to June 2020 in Cameroon where this fish is distributed in native zones. This study aimed at contributing to the genetic characterization of Heterotis niloticus population in Cameroon. A total of 96 Heterotis niloticus were sampled from five regions namely Centre, South, Littoral, North and Far North. Caudal fins where randomly collected for genomic DNA (gDNA) extraction. Following standard procedures for simple sequence repeat markers available for this species, seven microsatellites were used for genotyping through Polymerase Chain Reaction (PCR) and electrophoresis. Genetic parameters were scored using the GenAlex 6.503 software and the population structure of Heterotis niloticus was assessed under STRUCTURE Version 2.3.4 software. The results showed that the local pop ulation of Heterotis niloticus in North-Cameroon has a higher number of allele (Na=6.00) and effective number of allele (Ne=3.66) while the highest Observed Heterozygosity (Ho) was observed for the population of Heterotis niloticus in the Far-North. The highest genetic distance is observed between the population of Far North and Centre, Far-North and South, Far-North and North. In general, similarity within the sub-population of Heterotis niloticus is higher than 65%. Genetically, the population of Heterotis niloticus in Cameroon was grouped into three genetic sub populations based on microsatellites appraisal. Further investigations are suggested for analysis concerning productive traits for domestication and aquaculture purposes.