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Ataxia with vitamin E deficiency
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Condition

Ataxia with vitamin E deficiency

Ataxia with vitamin E deficiency is a rare inherited disorder that impairs the body's ability to use dietary vitamin E, leading to progressive neurological problems.

Overview

Vitamin E acts as an antioxidant, protecting cells from damage caused by free radicals. A deficiency in this vitamin leads to neurological impairment, typically manifesting between the ages of 5 and 15. Symptoms include:

  • Ataxia: Difficulty coordinating movements.
  • Dysarthria: Difficulty with speech.
  • Lower limb areflexia: Loss of reflexes in the legs.
  • Peripheral neuropathy: Loss of sensation in the extremities.
  • Retinitis pigmentosa: An eye disorder that can cause vision loss.

Causes

The condition is caused by mutations in the TTPA gene, which provides instructions for making the α-tocopherol transfer protein (αTTP). This protein is responsible for distributing vitamin E from the liver to tissues throughout the body.

Mutations in TTPA impair the activity of αTTP, resulting in low blood levels of vitamin E and the accumulation of free radicals. Nerve cells in the central nervous system are particularly vulnerable to this oxidative damage, leading to the progressive movement problems associated with the disorder.

Inheritance

This condition is inherited in an autosomal recessive pattern. Both copies of the gene in each cell must have mutations for the disorder to occur. Parents of an affected individual each carry one copy of the mutated gene but typically do not exhibit symptoms.

Frequently Asked Questions

Diagnosis starts with a serum α‑tocopherol level that is markedly low (often <5 µg/dL) after a normal diet. Because low levels can be secondary to malabsorption, a genetic test for pathogenic variants in the TTPA gene is performed to confirm the inherited form. Nerve conduction studies and ophthalmologic exams help document the extent of neuropathy and retinopathy.
High‑dose oral vitamin E (800–1200 IU/day) or intramuscular preparations can raise blood levels and often stabilizes or modestly improves gait and speech if started early. However, established neuropathy and retinal degeneration are usually only partially reversible; early treatment is critical to prevent further decline.
The first clues are usually clumsiness or frequent falls, difficulty walking in a straight line (gait ataxia), and a slurred or nasal speech (dysarthria). Loss of deep tendon reflexes in the legs, tingling or numbness in the feet, and trouble with fine motor tasks (e.g., buttoning) often appear before age 15. Vision problems such as night blindness may develop later.
Because the disorder is autosomal recessive, each sibling of an affected child has a 25 % chance of being affected, a 50 % chance of being a carrier, and a 25 % chance of being unaffected and not a carrier. Offer carrier testing to parents and, if they wish, predictive testing (serum vitamin E level and TTPA sequencing) to siblings. For future pregnancies, prenatal or pre‑implantation genetic diagnosis is available if the family’s specific mutations are known.===
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

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