We determined the effects of Parkinson's disease-associated mutations on PINK1 catalytic activity by selecting 14 homozygous or compound heterozygous missense mutations that lead to early-onset Parkinson's disease in which the disease-associated amino acid residue is conserved in TcPINK1 (figure 4a; electronic supplementary material, table S1). Here, PINK1 is linked to Parkinson disease.