Families

How common it is:
We do not yet know how many people are affected.

How it’s inherited:
It follows an X-linked recessive (XLR) pattern, meaning that females can carry the gene without showing symptoms, while males are more likely to be affected.

Main symptoms:
Most children have delays in language and movement development, and some may be diagnosed with autism spectrum disorder (ASD).
Seizures are common, including different types like jerking (clonic), stiffening (tonic), full-body seizures (tonic-clonic), or brief staring spells (atypical absences). These seizures can be hard to control with medication. Brain activity tests (EEGs) may show unusual patterns.
Brain scans (MRI) usually look normal.