Imprecise excision of the P{EP} element, resulting in a 2096bp deletion beginning at the site of the insertion in exon 1 and extending into exon 4 of the Mnn1 gene.
Although Mnn1e30 mutants are viable in control conditions, they show a high degree of lethality when subjected to heat shock, hypoxia, and oxidative stress. Mnn1e30/Df(2L)spdj2 show similar levels of lethality in response to heat shock.