Over the past two decades, large-scale genomic studies have revealed the presence of 4 molecular entities among MBs, consisting of wingless/Int (WNT), sonic hedgehog (SHH), group 3, and group 4 that can be stratified according to their distinct genomic, epigenomic, transcriptomic, or proteomic characteristics (3–8). The gene discussed is SHH; the disease is Mobius syndrome.