Among the loss-of-function mutations which cause recessive EOPD such as PRKN, PINK1, DJ-1 and ATP13A2 [8,9], homozygous and compound heterozygous mutations in the PRKN gene are responsible for approximately half of recessive-inheritance PD families with onset before the age of 45 years [6]. This evidence concerns the gene PRKN and Parkinson disease.