Any Coffin-Siris syndrome in which the cause of the disease is a mutation in the ARID1A gene. The disease is MONDO_0013819 (intellectual disability, autosomal dominant 14). Also known as: ARID1A Coffin-Siris syndrome, ARID1A-related BAFopathy, CSS2, Coffin-Siris syndrome caused by mutation in ARID1A, MRD14, autosomal dominant intellectual disability 14, autosomal dominant mental retardation 14, intellectual disability, autosomal dominant type 14.