CRISPR/Cas9 engineered deletion of fzy-1 in which the fzy-1 coding sequence was replaced by LoxP. Homozygous lethal deletion chromosome balanced by GFP- and dpy-10-marked inversion. Heterozygotes are wild-type with relatively dim pharyngeal GFP signal, and segregate wild-type dim GFP (heterozygotes), Dpy bright GFP (mIn1 homozygotes), and non-GFP fzy-1 homozygotes (larval arrest). Pick wild-type with dim GFP and check for correct segregation of progeny to maintain. gRNA sequence: Ggacgcacgcccggtagtgc Reference: Kim T, et al. Genes Dev. 2017 Jun 1;31(11):1089-1094. doi: 10.1101/gad.302067.117. PMID: 28698300.