ENZYME POLYMORPHISMS IN ASCARIS-LUMBRICOIDES IN BANGLADESH

Fourteen enzymes of Ascaris lumbricoides were analysed electrophoretic ally on cellulose acetate plates; 8 stained well and 3 were found to b e polymorphic. Allelic and genotypic frequencies at the 3 polymorphic enzyme loci, Mpi, Pgi and 6-Pgd, were determined in a sample of 117 wo rms from 8 children living in different houses in an urban slum in Ban gladesh. Allele frequencies in samples of parasites from the different children were compared to test for the possibility of non-random dist ribution of parasite genotypes between people. No strong evidence of d ifferences was found. Diploid genotype frequencies did not deviate sig nificantly from those expected from the Hardy-Weinberg equilibrium. Si gnificant linkage disequilibrium was observed in one of 3 pairs of enz yme loci tested, which might suggest that some genetic subdivision exi sts in the local A. lumbricoides population, although no strong interf erence should be made from this single result. Overall, the results su ggest that the worms sampled formed part of a single population which appears to be randomly mating.