Patients with Rubinstein-Taybi syndrome (RSTS) [OMIM #180849] have characteristic facial features, short stature, broad (often angulated) thumbs and great toes, and moderate to severe mental retardation. Characteristic facial features include arched eyebrows, down-slanting palpebral fissures, a beaked nose with long columella, high arched palate, and grimacing smile. Mutations of the CREBBP (CREB binding protein) [OMIM #600140] gene have been identified in patients with RSTS. Approximately 10% of patients with RSTS have 16p13.3 microdeletions involving the CREBBP gene, 30-50% of patients with RSTS have mutations in the CREBBP gene, and approximately 10-20% of patients with RSTS have intragenic deletions or duplications involving one or more exons of CREBBP.
Deletions and/or duplications in the CREBBP gene as causative of Rubinstein-Taybi syndrome have been reported.