Exon 6 was targeted with an sgRNA (targeting GGTTGTGAGCGCAGGCATGC) and an ssODN template (ACAGCCAAAAATCTCGATTGTTTCTCCTTAGAAAATCCCAGAGCAGAGTGTCTTATTACACGCATGTGCACACAACCCCACCGGCGTGGACCCGCGTCCCGAGCAGTGGAAGGAGATAGCGTCCG) using CRISPR/Cas9 technology to delete one of leucine codons 207, 208 or 209 (p.L209del). The equivalent human mutation (p.Leu209del, NM_002080.2:c.624_626delTCT) is found in some Malate-Aspartate Shuttle (MAS)-Related Encephalopathy patients. (J:291216)