Autosomal recessive
Caused by changes in both copies of VARS1, the enzyme that attaches the amino acid valine to its transfer RNA for protein production. Missense changes are thought to disrupt its catalytic and tRNA-binding regions, and some variants cause loss of function.
Signs and symptoms
Progressive microcephaly, seizures, which can be intractable, and developmental delay or intellectual disability are typical.
What a diagnosis changes
Seizure management, feeding support and developmental therapies, coordinated by a neurologist. Carrier testing of relatives and genetic counselling are available.
Genes analysed
Also known as
NDMSCA
