PTRHD1 and Parkinson disease: New genes forautosomal recessive disease include SYNJ1,DNAJC6, VPS13C, and PTRHD1. Deletions ofa region on chromosome 22 (22q11.2del) are also associated with early-onset PD,but the mode of inheritance and the underlying causative gene remain unclear.PODXL mutations were reported in autosomalrecessive PD, but their roles remain to be confirmed.