Finally, there have been in vitro and in vivo models of Mandibulofacial Dysostosis Guion-Almeida type (MFDGA), caused by haploinsufficiency of EFTUD2, the craniofacial disorder with the strongest phenotypic overlap with BMKS and the strongest genetic link as both disorders are caused by U5 snRNP gene variants [58–60,96,97]. This evidence concerns the gene EFTUD2 and mandibulofacial dysostosis-microcephaly syndrome.