Discovery of the PLA2G6 gene, whose mutated forms trigger several genetic disorders categorized as neuroaxonal dystrophies, could shed light on the nerve cell degeneration that leads to such neurological maladies as Parkinson's and Alzheimer's diseases, both known to be associated with brain iron accumulation.
"If you're a family with a kid with one of these diseases, the impact is clear, specific and personal," said Susan J. Hayflick, M.D., professor of molecular and medical genetics, pediatrics and neurology in the OHSU School of Medicine. But because it may heighten understanding of other, better-known neurological disorders, "To the general population, (the discovery) has a larger impact, and that's a significant benefit."
In a study published online June 18 in the journal Nature Genetics, Hayflick and an international team of geneticists describe PLA2G6's discovery using DNA from families with infantile neuroaxonal dystrophy, or INAD, and a related disorder known as neurodegeneration with brain iron accumulation, or NBIA.
In INAD, also known as Seitelberger disease, symptoms start by age 2 and worsen over time, and include loss of head control and the ability to sit, crawl or walk, as well as deteriorating vision and speech, according to the National Institute of Neurological Disorders and Stroke, a branch of the National Institutes of Health. Children with the disease die between ages 5 and 10.
NBIA, sometimes called Hallervorden-Spatz syndrome, manifests itself between the teen years and adulthood. Symptoms include involuntary muscle contractions, rigidity and spasms in the limbs, face and torso, as well as confusion, disorientation, seizures, stupor and dementia. Rapid deterioration, punctuated by stable periods, lasts on
Contact: Jonathan Modie
Oregon Health & Science University