(↑) In DOPAn, microglia, and astroglia of the SN. (↑) In neurons of the neo-cortex with Lewy bodies.(↑) In in vitro model of PD.Genetic variants of HMOX1 (leading to a reduced transcription and induction of the gene) are more frequent in PD subjects and correlate with an early onset of the disease. This evidence concerns the gene HMOX1 and Parkinson disease.