Abstract
A suite of aberrant genetic traits, including increased mutation rate, sex-limited mutation and distorted transmission ratios, was produced among progeny of genetic crosses between two strains ofDrosophila mauritianawhen a paternally contributedMosexcision factor is placed into a non-Mosgenetic background. In the reciprocal cross, involving maternally contributedMosandMosassociated cytoplasm, the same genetic abnormalities are not observed. Differential effects onmarinerexcision in germ-line versus somatic tissue are apparent. BecauseMosis known to influence the mobility of themarinertransposable element, these traits may be associated withmarinerexcision and/or transposition.