Coffin-Siris syndrome [CSS OMIM #135900] is characterized by developmental delay, coarse facial features, speech impairment, hypertrichosis, hypoplastic or absent fifth fingernails or toenails, and agenesis of the corpus callosum. Other findings can include failure to thrive, feeding difficulties, short stature, ophthalmologic abnormalities, microcephaly and hearing loss.
Tsurusaki et al, 2012 identified de novo mutations in SMARCB1 in 2/5 individuals with CSS. SMARCB1 encodes a subunit of the SWItch/Sucrose Non-Fermenting (SWI/SNF) complex, and screening of additional genes encoding subunits of this complex revealed mutations in SMARCA2, SMARCA4, SMARCE1, ARID1A andARID1B. Overall, Tsurusaki et al, 2012 identified mutation in 20/23 (87%) patients with CSS. Mutations in SMARCA2 have since been identified in patients with Nicolaides-Baraitser syndrome.
Our Coffin-Siris syndrome Del/Dup Panel includes analysis for all of the following 6 genes: ARID1A, ARID1B, SMARCA2, SMARCA4, SMARCB1, SMARCE1