Two monoallelic mutations in the 5′ region of Nurr1 gene (c.-291delinsT and c.-245T>G) have been shown to be associated with PD, those mutations reduced the expression of Nurr1 [23], a homozygous 7048G7049 polymorphism was found in intron 6 of the Nurr1 gene in association with PD [24], a missense mutation (S125C) in Nurr1 has been described in a PD patient [25] and a single base substitution in the 5′-UTR (c.-309C>T) correlated with a decrease in Nurr1 mRNA expression has also been described in PD patients [26]. The gene discussed is NR4A2; the disease is Parkinson disease.