The strain of Drosophila melanogaster carrying the inversion of In(1)wm4, which juxtaposes the normal w+ gene to the centromeric heterochromatin, variegages for pigmentation in the eye. This strain was treated with various concentrations of n-butyrate and n-proprionate during the embryonic and larval stages. Concentrations as low as 70 mM markedly suppress the variegated eye phenotype. This suggests that non-acetylated histones play a major role in the phenomenon of position-effect variegation.