Rubinstein-Taybi syndrome in first cousins with different de novo mutations.

摘要

The Rubinstein-Taybi syndrome (RTS, OMIM 180849), first described in 1963, is a rare autosomal dominant disorder characterized by typical facial appearance, broad and deviated thumbs and great toes, short stature, and mental retardation. The RTS can be caused by mutations in the CREBBP and EP300 genes. The vast majority of the mutations were found to be de novo and familial occurrence of RTS in more than one individual is extremely rare [Hennekam et al., 1990]. Very recently, Chiang et al. [2009] demonstrated germ-line mosacism in one family where two siblings had the same mutation but no mutation was present in either parent. In a second family, the father of one affected child displayed low-level mosaicism for a CREBBP mutation. The authors concluded that further studies are necessary to determine the frequency of somatic and/or gonadal mosaicism in RTS [Chiang et al., 2009].