Autosomal dominant
Caused by loss-of-function changes in one copy of KMT2A, a chromatin regulator that controls the activity of many developmental genes. Most cases arise de novo, though inheritance from an affected parent has been reported.
Signs and symptoms
Developmental delay and intellectual disability, with marked variability between people, and low muscle tone and short stature. Extra hair on the elbows, back and limbs, and distinctive facial features such as thick eyebrows and long eyelashes, are characteristic. Other features reported include seizures, feeding problems, behavioural differences and heart defects.
What a diagnosis changes
Developmental, educational and behavioural support, with monitoring of growth, feeding, eyes and heart. Most cases arise de novo, but genetic counselling and parental testing help clarify recurrence risk.
Genes analysed
Also known as
A syndrome of abnormal facies, short stature, and psychomotor retardation; hypertrichosis-short stature-facial dysmorphism-developmental delay syndrome; WDSTS; Wiedemann Grosse Dibbern syndrome
