Inducible nitric oxide synthase (NOS2A) may be involved in the oxidative stress pathology of Parkinson disease (PD). Two previous studies reported an association of a single nucleotide polymorphism (rs1060826) with PD. A replication study of 340 German patients and 680 controls showed no significant association between 12 genotyped polymorphisms and PD. NOS2A is therefore not a major susceptibility locus in our relatively young sample population.