In addition to MECP2, other genetic variants have been identified as contributing to RTT-like phenotypes, including CDKL5 and FOXG1, MEF2C, TCF4 [19, 20], CTNNB1, WDR45 [21], ATP6V0A1, USP8, MAST3, and NCOR2 [22]. The gene discussed is MECP2; the disease is Rett syndrome.