ADNP and Coffin-Siris syndrome: Understanding ADNP’s mediating role in the formation of the (SWI/SNF) remodelling (BAF) complex, it is not surprising that the Helsmoortel–Van der Aa syndrome shares phenotypic similarities with BAFopathies [8,9,10], such as Coffin–Siris syndrome (MIM 135900), with the following common features: developmental delay; gastrointestinal problems; visual impairment; hypotonia; central nervous system abnormalities; a small or hypoplastic distal phalanx of the 5th fingers; facial similarity [1,17].