An electrophoretic study of protein diversity in five species of land snails (Achatinidae) from Nigeria

The protein profile of five species of achatinid snails (Archachatina marginata (Swainson, 1821), Achatina achatina (Linnaeus, 1758), Achatina fulica (Bowdich, 1822), Archachatina papyracea (Pfeiffer, 1845) and an unidentified snail species) from some parts of southern and north-central states of Nigeria was used to examine the level of genetic similarity between them and also to show whether the eight populations of Archachatina marginata studied contained sub-populations. Each of the species examined was found to have unique protein bands while the protein banding patterns of the eight populations of A. marginata showed six of the populations being taxonomically distinct because they had unique protein bands. The cluster analysis of the A. marginata samples produced two sub-species which showed geographical separation of the species. This may depict a relationship between total protein and ecological adaptation. However, there was better resolution of the protein band patterns using relative mobility of bands. The presence of common bands among the species and the eight populations of A. marginata may depict an evidence of evolutionary origin of the species studied. © 2013 International Formulae Group. All rights reserved.Keywords: Achatina spp., Archachatina spp., protein, electrophoresis, taxonomy

Genetic differentiation and inheritance of random amplified polymorphic DNA (RAPD) markers in pectoral spine phenotypic sub-groups of Clarias gariepinus

Information on genetic relationship of phenotypically divergent sub-groups would be useful for better identification, utilization and management of species. Recent study revealed phenotypic divergence in a reservoir population of Clarias gariepinus. Genetic variability of polymerase chain reaction (PCR) products of the phenotypic divergent sub-groups was investigated in this study. Polymorphism and genetic variability were investigated in electrophoresed random amplified polymorphic DNA (RAPD)-PCR products of blood samples of twenty (20) C. gariepinus individuals. The population comprised of five (5) individuals of the non-peses phenotypic sub-group- individuals that did not possess anteriorly serrated pectoral spines denoted by S and fifteen (15) individuals of peses sub-groups that possessed anteriorly serrated pectoral spines denoted as C. Standard protocols were followed in analyzing six screened RAPD primers per individuals DNA fragment. Produced bands of pheno-grams were scored and analyzed to establish polymorphism as well as within and between sub-populations allelic variability using unweighted paired group method of algorithms (UPGMA) and dendrograms cluster analysis. Genotype data of individuals in the groups were tested for canonically significant discriminant grouping using discriminant function analysis (DFA). Results reveal that the primers were polymorphic: 746 bands were obtained from 63 detected loci which gave 80.95% polymorphism. Polymorphic information content (PIC) ranged between 0.18 and 0.49. Percentage polymorphic band were 78.00 and 69.84% for peses and non peses sub-groups, respectively. Dendrogram separated the population to two groups. All peses individuals were in one cluster while all the non-peses individuals were on the second cluster. Within group variations were also observed: DFA revealed that 100% of original phenotypically grouped cases were correctly classified. It was concluded that RAPD primers are suitable genetic markers for establishing variability in C. gariepinus sub-populations; the pectoral spine phenotypic groups are genetic variants and are potential varieties for the species. The results would have wide application in identification, utilization and management of genetic resources of C. gariepinus.Keywords: Random amplified polymorphic DNA (RAPD) marker, morphologic and genetic variability, Clarias gariepinus.African Journal of Biotechnology Vol. 12(37), pp. 5567-557

Morphometric characteristics, survival and growth of hybrids between Claria anguillaris (Linaeus, 1758) and Heterobranchus longifilis (Valenciennes, 1840)

No Abstract.Nigerian Journal of Genetics Vol. 15 2000: pp. 46-5

Cytogenetic study and serum protein characterization of Clarias gariepinus (BURCHELL, 1822) and Heterobranchus bidorsalis (Geoffroy Saint-Hillaire, 1809) in South western Nigeria

Specimens of Clarias gariepinus and Heterobranchus bidorsalis were cytologically analysed while their serum protein was employed to characterize the two species. The diploid chromosome numbers for C. gariepinus and H. bidorsalis were 2n=56 and 2n=52 respectively. The nombre fondamental (NF) of C. gariepinus, and H. bidorsalis, were 51 and 49 respectively. The electrophoretic banding pattern of the two species produced five common bands while the relative mobility of the bands studied showed that there are few slow moving bands, more fast moving bands but no intermediate bands. The occurrence of chromosome number around the modal value which occurs generally among the clariid fish may suggest an ongoing speciation while the presence of five common bands may also be used as a diagnostic marker for biochemical differentiation of the two fish species.Keywords: Clarias gariepinus, Heterobranchus bidorsalis, diploid chromosome number, cytogenetics, genetic variation, electrophoresis