Incompletely-penetrant exploding vulva. wd26 (E580K) is an intragenic revertant of the e262 allele for the backward movement phenotype; it is not known if it also modifies other e262 phenotypes. The wd26 lesion (E580K) is molecularly identical to wd14, wd16, wd17, wd18, etc. Reference: Pflugrad A, et al. Development. 1997 May;124(9):1699-709.