A close connection between the SWI/SNF complex and neurological development has been implicated through the identification of numerous mutations in genes encoding the subunits in a range of neurodevelopmental disorders such as Coffin–Siris syndrome, sporadic intellectual disability, autism spectrum disorder, schizophrenia, and Kleefstra syndrome [Son and Crabtree, 2014]. The gene discussed is SMARCA1; the disease is Kleefstra syndrome.