Other Names for this Disease
- Pyridoxine dependency
- Pyridoxine dependency with seizures
- Vitamin B6-dependent seizures
What symptoms are associated with pyridoxine-dependent epilepsy?
What causes pyridoxine-dependent epilepsy?
How might pyridoxine-dependent epilepsy be treated?
Mutations in the ALDH7A1 gene cause pyridoxine-dependent epilepsy. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
The ALDH7A1 gene provides instructions for making an enzyme called α-aminoadipic semialdehyde (α-AASA) dehydrogenase, also known as antiquitin. This enzyme is involved in the breakdown of the protein building block (amino acid) lysine in the brain.
When antiquitin is deficient, a molecule that interferes with vitamin B6 function builds up in various tissues. Pyridoxine plays a role in many processes in the body, such as the breakdown of amino acids and the productions of chemicals that transmit signals in the brain (neurotransmitters). It is unclear how a lack of pyridoxine causes the seizures that are characteristic of this condition.
Some individuals with pyridoxine-dependent epilepsy do not have identified mutations in the ALDH7A1 gene. In these cases, the cause of the condition is unknown.
- Pyridoxine-dependent epilepsy. Genetics Home Reference (GHR). 2013; http://ghr.nlm.nih.gov/condition=pyridoxinedependentepilepsy. Accessed 7/23/2013.
- Gospe SM. Pyridoxine-Dependent Seizures. GeneReviews. 2012; http://www.ncbi.nlm.nih.gov/books/NBK1486/. Accessed 7/23/2013.
- van Karnebeek CD et al. Lysine restricted diet for pyridoxine-dependent epilepsy: first evidence and future trials. Mol Genet Metab. 2012 Nov;107(3):335-44. .