Currently, four genes are clearly involved in the autosomal dominant form of PD: the SNCA/PARK1- PARK4 gene, the LRRK2/PARK8 gene, the VPS35/ PARK17 gene, and the EIF4G1/PARK18 gene; on the other hand, PARK-1 and DJ-1 genes are typically involved in the autosomal recessive transmission. The gene discussed is LRRK2; the disease is Parkinson disease.