mus(3)312D1, A mutagen sensitive mutant with profound effects on female meiosis in Drosophila melanogaster.

The third chromosome, mutagen sensitive mutant mus(3)312D1 impairs the meiotic process in females by increasing the frequency of first division nondisjunction and decreasing the frequency of meiotic crossing over. These genetic properties connote 312 to be defective in DNA replication and/or repair intimately associated with the crossing over exchange process. The mutant maps to the left arm of chromosome III between ru and h, and represents a new genetic site for a meiotic mutant.