vr25 is a Crispr/Cas9-induced 56 bp deletion in exon 2 of oef-1/F49E8.2 causing a frameshift and presumptive null allele. Accelerated rate of germ cell progression, precocious Z2/Z3 division in L1s, increased brood size and sperm generation, and increased germline apoptosis. Reference: McManus, CE & Reinke, V. Genetics. 2017; https://doi.org/10.1534/genetics.117.1123.