Genotype-phenotype correlates in Taiwanese patients with early-onset recessive Parkinsonism.

We screened for mutations in the PARKIN, DJ-1, and PINK1 genes in a Taiwanese cohort (68 probands; 58 sporadic and 10 familial) with early-onset parkinsonism (EOP, onset <50 years of age). We identified 9 patients harboring mutations in PARKIN (three compound heterozygous and six single heterozygous carriers), 3 patients with heterozygous PINK1 mutations (including two novel substitutions M341I and P209A), and no DJ-1 mutations. Our frequencies of PARKIN (two allele mutation, 4.4%; single allele, 8.8%) and PINK1 (single heterozygous, 4.4%) mutations in Taiwanese-Chinese are similar to those in Caucasian and other Asian EOP patients. Although the role of heterozygosity of recessive genes in EOP remains to be resolved, molecular analysis and functional imaging will play a decisive role in differential diagnosis and determined therapeutic strategy.