A series of exome sequencing studies have uncovered dominant de novo BAF mutations in patients with Coffin-Siris syndrome (CSS), a rare congenital disorder with microcephaly, AgCC, moderate-to-profound ID, developmental delay, coarse facial features, hypoplasia of the fifth fingernails and/or toenails and multiple organ abnormalities (Tsurusaki et al., 2013, 2012; Santen et al., 2012, 2013; Wieczorek et al., 2013). In each of the large-scale studies, between 41–87% of the subjects were positive for BAF mutations. A combined total of 106 lesions have been reported in five subunits: BAF250A (8/106, 7.5%), BAF250B (72/106, 6.8%), BRG1 (12/106, 11.3%), BAF47 (12/106, 11.3%) and BAF57 (3/106, 2.8%)
