Autosomal dominant mental retardation-50

General Medical Guideline
Last modified
7 March 2020

NAA15 mutations are associated with having a variable degree of neurodevelopmental disabilities, including impaired motor abilities, intellectual disability, impaired verbal abilities, and an autism spectrum disorder.

Developmental delay

Impaired motor function, including fine-motor difficulties, mild ataxia, abnormality of movement, motor delay, and hypotonia should be evaluated and motor development may need to be stimulated.

Intellectual disability may be mild, moderate, or severe. Learning difficulties can be associated with or without behavioural issues. Each individual should be intellectual and behavioural evaluated. Learning possibilities supported.

Verbal issues may be severe including a complete absence of speech, delayed language development, the need for sign language, or other speech difficulties.

Most subjects also present with autism spectrum disorder (ASD).

A marked hypersomnolence in early years has been observed.

Dysmorphologies (typical physical features) can be present.  A recognizable pattern of dysmorphologies has not been defined.

Growth patterns have not been well established. Low birth weight and length are reported. Small had circumference is observed.

Cardiac anomalies are reported. Since there may be a subset of individuals with an elevated risk of a cardiac anomaly, a cardiac evaluation could be recommended.

Cheng et al 2018

Zhao et al 2017

Rare Condition

Autosomal dominant mental retardation-50

Autosomal dominant mental retardation-50 is associated with NAA15 gene mutations in large cohorts of DNA samples of people with mild to severe developmental delay and/or...