CRISPR-Cas9 technology generated a 2 base pair deletion (c.969_970delCT) in the alternatively-spliced micro-exon 4 (equivalent to micro-exon 3 in human) resulting in a substitution of threonine for serine at residue 324 followed by a translation frameshift resulting in a premature translation stop codon three codons downstream (S324Tfs*3). This is one of the pathogenic variants associated with early infantile epileptic encephalopathy. (J:273646)