CRISPR/Cas9 technology was used to introduce an alanine for threonine substitution at codon 991 (T991A) in exon 22. The T991A mutation has been identified in a patient with severe peripheral neuropathy, abolishes Thr991 phosphorylation, is a gain of function mutation and results in constitutive activity. This line corresponds to line #31. (J:259728)