Homozygous viable. mev-1(tr399) is a C197T (T66I) missense mutation. mev-1 also known as sdhc-1. Isolated in an F1 screen for resistance to the lethality induced by wact-12. Reference: Burns AR, et al. Nat Commun. 2015 Jun 25:6:7485. doi: 10.1038/ncomms8485. PMID: 26108372.