Gene Mutation Can Accelerate Parkinson Disease Onset
Age of onset lower by at least 12 years
MONDAY, June 12 (HealthDay News) -- Mutations in the parkin gene can accelerate the development of Parkinson disease by 12 or more years, according to a study in the June issue of the Archives of Neurology.
James F. Gusella, Ph.D., from Massachusetts General Hospital in Boston, and colleagues identified 183 families where at least one member had developed Parkinson disease before the age of 54, or where two affected siblings had two identical alleles of the parkin gene. At least one member of each family was screened for abnormalities in the parkin gene.
The researchers found mutations in the parkin gene in 12.6 percent of the families, with 43 percent of these having a member with two different mutations (compound heterozygotes), 13 percent having a member with two copies of the same mutation (homozygotes), and 43 percent having a member with one normal and one mutated gene (heterozygotes). The age of onset of Parkinson disease was significantly lower in patients with one mutation in the parkin gene (by 11.7 years compared with no mutations) and in patients with two or more mutations (by 13.2 years compared with one mutation), according to the study.
The findings "are provocative and add a new genetic dimension to the pathogenesis of Parkinson disease," Uwe Beffert, Ph.D., and Roger N. Rosenberg, M.D., from the University of Texas Southwestern Medical Center in Dallas, write in an accompanying editorial.