Frameshift mutation hotspot identified in Smith-Magenis syndrome: case report and review of literature

BMC Medical Genetics

Table 1 Phenotypic features of Smith-Magenis syndrome patients with a 17p11.2 deletion or RAI1 mutation.

Clinical findings	17p11.2 deletion (%)*	RAI1 mutation (%)*	SMS324	SMS335
Craniofacial/skeletal
Brachycephaly	89	81.8	+	+
Midface hypoplasia	92	72.7	+/-	+
Prognathism (relative to age)	53	88.8	-	-
Tented upper lip	73	91.6	+	-
Broad square face	81	90.9	+	+
Synophyrys	62	33.3	+	-
Cleft lip/palate	9	0	-	-
Brachydactyly (short fingers, toes)	85	83.3	+	+
Short stature	69	9	+	+
Scoliosis	49-67	36.3	+	+
Otolaryngologic
Chronic ear infections	85	54.5	N	+
Hearing loss	68	10	+	+
Horse, deep voice	80	100	+	-
Neurological/behavioral
Intellectual disability	100	100	+	+
Speech delay	>90	70	+	+
Motor delay	>90	70	-	+
Hypotonia	>90	61	+	+
Seizures by history	11-30	16.6	+	-
Sleep disturbance	70-100	100	+	+
Self-hugging/hand-wringing	70-100	100	-	-
Attention-seeking	80-100	100	+	+
Self-injurious behaviours	78-96	100	+	+
Onychotillomania	25-85	80	-	+
Polyemboilokomania	25-85	90	-	+
Head-banging/face-slapping	71	60	+	-
Ocular
Myopia	53	60	+	-
Strabismus	50	40	+	+

*Modified from Girirajan et al. 2007; + = present, - = absent, N = unknown/not evaluated

ISSN: 1471-2350