Complete inactivation of the hypomorphic targeted allele was observed when a gene editing strategy for ornithine transcarbamylase deficiency was tested in adult Spf-Ash mice, as the DSB was corrected mainly by NHEJ, worsening the phenotype of treated mice (Yang et al., 2016). Here, SEC14L2 is linked to hyperinsulinemic hypoglycemia, familial, 4.