Autosomal recessive
Chudley-McCullough syndrome is caused by changes in both copies of GPSM2, a gene that controls the orientation of cell division, which matters for the inner ear and the developing brain.
Signs and symptoms
Severe to profound sensorineural hearing loss, usually present from birth or early childhood, is the main feature. Brain imaging typically shows partial absence of the corpus callosum, cerebellar differences, clusters of misplaced nerve cells in the frontal lobes, enlarged fluid spaces in the brain (ventriculomegaly) and sometimes arachnoid cysts. Most people have normal or only mildly affected development.
What a diagnosis changes
Early hearing support, including hearing aids or cochlear implants, and language support are important. Genetic counselling is recommended; parents are usually carriers, each future child has a 1 in 4 chance of being affected, and carrier testing can be offered to relatives.
Genes analysed
Also known as
CMCS; deafness, autosomal recessive 82; deafness, bilateral sensorineural, and hydrocephalus due to foramen of Monro obstruction; deafness, sensorineural, with partial agenesis of the corpus callosum and arachnoid cysts
