FOCAL CORTICAL DYSPLASIA

GENETICS

PATTERN OF INHERITANCE

De novo gene abnormalities are implicated. These are mostly somatic mutations, but germline mutations can occur. Familial cases are reported only exceptionally.

KNOWN GENES

Recently gene abnormalities in mTOR pathway genes have ben found in some patients with FCD type II. These gene abnormalities may be germline (DEPDC5 and NPRL3) or somatic (TSC2).

FAMILY HISTORY

Rare familial cases of FCD have been reported in patients with gene abnormalities in DEPDC5 or NPRL3 genes. There is variable expressivity in these patients, with some family members seemingly unaffected, others with focal epilepsy and normal MRI and others with FCD.