Two new loci, PARK6 and PARK7, for autosomal recessive early-onset parkinsonism have recently been identified on chromosome 1p, in single large pedigrees. Among 4 autosomal recessive early-onset families analyzed here, 2 supported linkage to PARK7, 1 with conclusive evidence. These data confirm localization of autosomal recessive early-onset parkinsonism to PARK7, suggesting it to be a frequent locus. Assignment of families to either PARK6 or PARK7 might be difficult because of the proximity of the two loci on chromosome 1p.