Mutations in DDX3X are a common cause of unexplained intellectual disability with gender-specific effects on Wnt signaling

Original research article by Snijders Blok et al. (2015).

Read the abstract here.

This article considers the effect that changes in the DDX3X gene have on females’ behavioral, developmental, and physical features. Participants were females with unexplained intellectual disability (ID). ID affects 1% to 3% of the human population and is more commonly reported in males than in females. The majority of genetic changes associated with ID occur in males. However, changes in the DDX3X gene are more commonly associated with ID in females. This study identified 38 females with de novo (new) DDX3X changes and analyzed their characteristics. The following table lists the common characteristics the researchers observed:

Clinical Features of Females with a DDX3X Gene Change
	Percentage (%)	Number of individuals with condition
Development
Intellectual disability or developmental delay	100	38/38
Mild or mild-moderate disability	26	10/38
Moderate or moderate-severe disability	26	10/38
Severe disability	40	15/38
Developmental delay	8	3/38
Growth
Low weight	32	12/38
Microcephaly	32	12/38
Neurology
Hypotonia	76	29/38
Epilepsy	16	6/38
Movement disorder (including spasticity)	45	17/38
Behavior problems	53	20/38
Brain MRI
Corpus callosum hypoplasia	35	13/37
Cortical malformation	11	4/37
Ventricular enlargement	35	13/37
Other
Skin abnormalities	37	14/38
Hyperlaxity	37	14/38
Visual problems	34	13/38
Hearing loss	8	3/38
Cleft lip or palate	8	3/38
Precocious puberty	13	5/38
Scoliosis	11	4/38