GENETIC VARIABILITY IN POPULATIONS OF DROSOPHILA MELANOGASTER ACROSS NIGERIAN SAVANNA ZONES

Drosophila melanogaster has been considered the best biological model for studies in areas such as genetics, behavior, evolution, development, molecular biology, ecology, and population biology. We studied the Genetic variability of Drosophila melanogaster sampled from Savanna zones of Nigeria using seven random microsatellites from previously characterized markers. The amplified fragments of 42 D. melanogaster from six populations across the three zones were analyzed and scored using the Image Lab TM and GenAlex 6.05 software. The three zones revealed high gene diversity (He = 0.5) which could be due to the high gene flow observed within a zone, Polymorphism Information Content (PIC) of 0.693, indicating a good discrimination power of the selected markers. The populations also did not deviate from Hardy-Weinberg Equilibrium (0.157) as shown by the difference between observed and expected heterozygosities. The genetic variation observed as indicated by AMOVA was mostly variations within the populations (91%), 9% among zones. The negative fixation indices ( F IS of -1.000 and F IT of -0.675) indicated an excess of heterozygotes in the subpopulations and outbreeding in the total populations respectively.  The study, therefore, reveals that the used markers are highly polymorphic (PIC˃0.5), the populations of D. melanogaster are highly genetically diversified, outbreeding and highly sub-structured.