Genetic Characterization Based on Rapd-Pcr in Cultured Strains of Clarias gariepinus (Siluriformes: Clariidae)

Abstract

The genetic polymorphisms of catfish populations collected from four fish farms in four Southwestern states of Nigeria were determined by Randomly Amplified Polymorphic DNA Polymerase Chain Reaction technique. This was to characterize the strains genetically and provide information on the studied catfish. Following standard procedures, polymerase chain reaction was performed by mixing 15 μl reaction mixture containing FIREPOL® Taq DNA polymerase, MgCl2, dNTPs, distilled water, dyes and glycerol, with 1.0 μl DNA sample of 16-week old C. gariepinus strains using OPA03, OPA04, OPC02, OPB08, OPC11, OPG16, OPG19 and OPA19 primers. A sum of 1708 loci having 3072 bands was amplified in all the samples. The RAPD analysis revealed significant genetic variability (P<0.05) among the four sampled populations. The unweighted pair group method with average (UPGMA) dendrogram based on Nei’s unbiased genetic distance matrix separated the Clarias gariepinus populations into two clades. The first clade was made up of populations from Ibadan and Abeokuta while the second clade consisted of populations from Ado-Ekiti and Ile-Ife. Thus, it is imperative to determine the genetic variation and population structure of the stocks of C. gariepinus in advance before commencing on breeding programmes.