Ab(2;3)T-1 significantly represses the occurrence of P-induced dysgenic sterility compared to controls in crosses of Ab(2;3)T-1 females to P males. A stronger repression of P-induced dysgenic sterility is seen if the Ab(2;3)T-1 females are also carrying P{lArB}A171.1F1. The array of P{lacW} element on Ab(2;3)T-1 can repress germline expression of other P{lacZ} insertions, either located on the same chromosome at a different site, or on a different chromosome. Repression is detected only when the Ab(2;3)T-1 chromosome is maternally inherited.

Enhancement of w variegation from the transgene array P{lacW}50C.x7. Enhancement is specific for the transgene array at 50C, it does not result from mutations in modifiers of PEV (chromosomes with and without the transgene array fail to enhance variegation of w in either In(1)w^m4 or P{lacW}92E.x3).