Autosomal dominant
Caused by changes in one copy of NFIX that produce an abnormal protein interfering with the normal one, rather than simply reducing it (which causes the related Malan syndrome). The reported changes have arisen de novo.
Signs and symptoms
Bones mature faster than usual, and growth is often poor, with failure to thrive at birth reported in some. Intellectual disability and distinctive facial features are typical. Other features reported include a prominent forehead, shallow eye sockets and pectus excavatum.
What a diagnosis changes
Care is supportive, with monitoring of bones and development. As reported cases have arisen de novo, recurrence risk is low, but genetic counselling and parental testing are still recommended.
Genes analysed
Also known as
accelerated skeletal maturation-facial dysmorphism-failure to thrive syndrome; MRSHSS
