SMARCE1 and Coffin-Siris syndrome: Variants in the SMARCE1 gene are known to cause Coffin–Siris syndrome (CSS5; Coffin–Siris syndrome 5, OMIM 616938), which is a rare congenital syndrome affecting many organs, characterized by moderate to severe intellectual disability (Kosho & Okamoto, 2014; Santen, Emmelien, Vulto‐van Silfhout, Pottinger, & Van Bon, 2013).