An analysis of centric and heterochromatic effects on recombination in drosophilia melanogaster

The effects of the telomere, centromere, and centric heterochromatin on recombination were assessed using two paracentric inversions, scute-4 (sc4) and scute-8 (sc8) in both homozygous and heterozygous combination. The centromere effect was verified by the results, with regions brought by inversion into close proximity to the centromere exhibiting reduced recombination. In addition, this study suggests that heterochromatin acts as a buffer zone with respect to the inhibitory effects of the centromere and telomere. An intrachromosomal effect of inversions on recombination was noted in the sc4 /sc8 studies, indicating that synapsis and recombination were entranced by structural heterozygosity in the heterochromatic regions of these chromosomes. Heterochromatic recombination was tested in inversion sc8 homozygotes and in sc4/sc8 heterozygotes with results indicating that heterochromatin does not recombine more readily when removed from centric inhibitions.