This genomic region includes a third critical gene called LETM1 (leucine zipper/EF-hand-containing transmembrane) associated with the neuromuscular features of WHS patients such as seizures disorders [5,51], and partially the WHSC1. Moreover, recent studies suggest that the fibroblast growth factor receptor-like 1 (FGFRL1) represents a plausible candidate gene for part of the craniofacial phenotype of WHS [47,52]. This evidence concerns the gene NSD2 and epilepsy.