This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
X-linked periventricular heterotopia or FLNA-related periventricular nodular heterotopia is a genetic disorder in which nerve cells in the brain do not migrate properly during early fetal development (a neuronal migration disorder). It is characterized by the presence of clumps of neurons near the brain’s ventricles. Most people with this disorder are female, as it can be lethal in males.
Symptoms typically begin with seizures in the teenage years. Intelligence is usually normal, but mild intellectual disability (including difficulty with reading and spelling) may occur. People with this condition also appear to be at increased risk for stroke and other vascular or coagulation (clotting) problems. Some people also have hyperflexible joints and vascular anomalies, which also occur in Ehlers-Danlos syndrome (EDS).
X-linked periventricular heterotopia is caused by mutations in the FLNA gene and is inherited in an X-linked dominant manner. Treatment depends on the symptoms in each person and typically includes anti-seizure medications.
EDS with periventricular heterotopia, previously considered a variant of EDS, is now considered to be the same as X-linked periventricular heterotopia type 1 (PVNH1) and is not included as an EDS subtype under the 2017 classification of EDS.
For more information, visit GARD.