Comparative studies of the genomes of Clarias gariepinus, Heterobranchus bidorsalis, and their hybrid using hydroxyapatite chromatography

Abstract

The study investigated the genomes of Clarias gariepinus, Heterobranhus bidorsalis and their hybrid. The elution pattern of C. gariepinus showed the presence of a low melting (AT rich) region between the temperatures of 60 °C and 70 °C. This very light fraction in Clarias showed as a minor shoulder in the DNA of the hybrid. There appeared to be so much integration of the genome of the two parental stocks in the Heteroclarias that the early melting fraction of the C. gariepinus DNA did not show prominently. The elution pattern of Heteroclarias DNA showed an intermediate pattern between those of H. bidorsalis and C. gariepinus, which however was tilted towards those of the Clarias DNA pattern. Also the melting temperatures of 79.2 °C, 83.0 °C and 82.0 °C obtained for H. bidorsalis, C. gariepinus and the hybrid respectively showed that the Tm of the DNA of the hybrid is intermediate between those of the parental stock.

Keywords: Genome, sonicate, unimodal, melting temperature (Tm)