Early onset parkinsonism (EOP) has been associated with mutations in the Parkin, PINK1, and DJ-1 genes. We studied the prevalence of mutations in all three genes in 127 unrelated Chinese patients with apparently sporadic EOP using direct sequencing analysis and real-time quantitative PCR analysis assay. There are 16 patients (12.6%) with mutations of Parkin gene, four patients (3.1%) with mutations of PINK1 gene, and three patients (2.4%) with mutation of DJ-1 gene. In conclusion, Parkin gene mutation is the most common pathogenic factor in Chinese patients with sporadic EOP. Mutations of DJ-1 and PINK1 gene are also found in Chinese patients with sporadic EOP.

Autosomal recessive early-onset Parkinsonism (AREP) has been associated with mutations in the Parkin, PINK1, DJ-1, and ATP13A2 genes. We studied the prevalence of mutations in all four genes in 29 Chinese unrelated families with AREP using direct sequencing analysis and real-time quantitative PCR analysis assay. There are 14 families (48.3%) with mutations of Parkin gene, 2 families (6.9%) with mutations of PINK1 gene, and 1 family (3.4%) with mutation of DJ-1 gene. No pathogenic mutations in ATP13A2 gene were found in these families. Three Parkin gene mutations (c.G859T, c.1069-1074delGTGTCC, and c.T1422C) and one DJ-1 gene mutation (c.T29C) have not been reported previously. In conclusion, Parkin gene mutation is the most common pathogenic factor in Chinese patients with AREP. Mutations of DJ-1 and PINK1 gene are also found in Chinese families with AREP. Mutations in ATP13A2 gene may be rare in Chinese families with AREP.