De Novo variants in the KMT2A (MLL) gene causing atypical Wiedemann-Steiner syndrome in two unrelated individuals identified by clinical exome sequencing

Table 1 Comparison of clinical features of patients with MLL- related WSS[9] with patient 1 and patient 2

System	Phenotype	WSS n = 5	Patient 1	Patient 2
Growth	Intrauterine growth restriction	3	-	/c
	Postnatal growth restriction	5	+ a	+d
Nervous	Developmental Delay	5	+	+
	Hypotonia	n.a.	+	+
	Mild Intellectual disability	5	+b	n.a.
Craniofacial	Strabismus	n.a.	+	-
	Microcephaly	2	- a	-d
	Wide anterior fontanelle	0	-	+
	Wide nasal bridge/broad nasal tip	5	+	+
	Downslanting/small palpebral fissures	5	+	+
	Hypertelorism	?	+	+
	Right microphthalmia	0	-	+
	Micrognathia	0	-	+
	Upper vermillion border thin	3	+	n.a.
Skeletal	Tapering fingers	3	+	+
	Broad 1^st digit	2	-	+
	Sacral dimple	4	+	+
	Rib anomalies (X-ray)	3	n.a.	n.a.
	2-3 Toe Syndactyly	0	-	+
	5^th finger clinodactyly	n.a.	+	n.a.
Integumentary	Hypertrichosis	5	/	-
	Hypertrichosis cubiti	5	/	-
	Long/thick eyelashes	5	+	+
	Thick eyebrows	5	+e	+
	Thick hair	n.a.	+	+

Legend: + Present; − Absent/questionably present; n.a. not ascertained. a. height (ht.), weight (wt.), head circumference (OFC) <3rd centile; b. IQ 65–75; c. birth wt. & OFC normal, ht. < 5^th centile. d. wt. and ht. (<3rd centile), OFC (<5th centile). e. synophris.

ISSN: 1471-2350