CDH23 and Usher syndrome type 1: This genetic alteration has been documented in other individuals diagnosed with KBG syndrome.[4] Also of interest, he was found to have 2 heterozygous variants of CDH23 (c.3179G > C (p.R1060P) and c.4210-2A > G), which were classified as variants of uncertain significance associated with Usher syndrome type 1- CDH23 related deafness.