Novel parkin mutations detected in patients with early-onset Parkinson's disease

A multiethnic series of patients with early‐onset Parkinson's disease (EOP) was studied to assess the frequency and nature of parkin/PARK2 gene mutations and to investigate phenotype–genotype relationships. Forty‐six EOP probands with an onset age of G, and exon 8‐9‐10 deletion. Homozygous mutations, two heterozygous mutations, and a single heterozygous mutation were found in 8, 6, and 1 patient, respectively. Heterozygous exon deletions represented 28% of the mutant alleles. The patients with parkin mutations showed significantly earlier onset, longer disease duration, more frequently symmetric onset, and slower disease progression than the patients without mutations, in agreement with previous studies. This study confirms the frequent involvement of parkin and the importance of genetic testing in the diagnostic work‐up of EOP. © 2004 Movement Disorder Society