Serine codon 365 (AGT) and threonine codon 368 (ACT) in exon 2 were changed to alanine (GCG) (p.S365A, p.T368A) using an sgRNA and an ssODN template with CRISPR/Cas9 technology. The mutations block phosphorylation of the residues in the encoded peptide. (J:277231)