Rescues at least partially the sensitivity to methyl methanesulfonate of mus309D2/Df(3R)T-7 and mus309D3/Df(3R)T-7 animals. Rescues at least partially the male and female sterility of mus309D2/Df(3R)T-7. Partially rescues the chromosome nondisjunction and chromosome loss phenotype of mus309D2/Df(3R)T-7 males.