Early‐onset Parkinson's disease caused by a compound heterozygous DJ‐1 mutation

Mutations in DJ‐1 have been linked to an autosomal recessive form of early‐onset parkinsonism. To identify mutations causing Parkinson's disease (PD), we sequenced exons 1 through 7 of DJ‐1 in 107 early‐onset (age at diagnosis up to 50 years) PD subjects. One subject had a frameshift mutation in the first coding exon and an exon 7 splice mutation both predicted to result in a loss of functional protein. This subject was diagnosed with probable PD at age 24 years with asymmetric onset and an excellent response to levodopa therapy. Our observations suggest that sequence alterations in DJ‐1 are a rare cause of early‐onset PD.