GTR Home > Conditions/Phenotypes > Heterotopia, periventricular, Ehlers-Danlos variant


Periventricular heterotopia is a condition in which nerve cells (neurons) do not migrate properly during the early development of the fetal brain, from about the 6th week to the 24th week of pregnancy. Heterotopia means "out of place." In normal brain development, neurons form in the periventricular region, located around fluid-filled cavities (ventricles) near the center of the brain. The neurons then migrate outward to form the exterior of the brain (cerebral cortex) in six onion-like layers. In periventricular heterotopia, some neurons fail to migrate to their proper position and form clumps around the ventricles. Periventricular heterotopia usually becomes evident when seizures first appear, often during the teenage years. The nodules around the ventricles are then typically discovered when magnetic resonance imaging (MRI) studies are done. Affected individuals usually have normal intelligence, although some have mild intellectual disability. Difficulty with reading and spelling (dyslexia) has been reported in some ... people with periventricular heterotopia. Less commonly, individuals with periventricular heterotopia may have more severe brain malformations, small head size (microcephaly), developmental delays, recurrent infections, blood vessel abnormalities, or other problems. Periventricular heterotopia may also occur in association with other conditions such as Ehlers-Danlos syndrome, which results in extremely flexible joints, skin that stretches easily, and fragile blood vessels. [from GHR] more

Available tests

15 tests are in the database for this condition. Compare labs offering these tests.

Check Associated genes and Related conditions for additional relevant tests.

Associated genes

  • Also known as: XX-FW83128A1.1, ABP-280, ABPX, CSBS, CVD1, FLN, FLN-A, FLN1, FMD, MNS, NHBP, OPD, OPD1, OPD2, XLVD, XMVD, FLNA
    Summary: filamin A, alpha

Clinical features

  • Pyloric stenosis
  • Thin skin
  • Cognitive impairment
  • Dilatation of the ascending aorta
  • Seizure
  • Joint hypermobility
  • Patent ductus arteriosus
  • Abnormality of the aortic valve
  • Abnormality of coagulation
  • Morphological abnormality of the central nervous system
  • Scoliosis
  • Patellar dislocation
  • Shoulder dislocation
  • Hernia
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