With the identification of more than 13 loci in 9 different genes associated with familial forms of PD,80 it is not surprising that numerous transgenic models of PD with abnormal production of PD-related proteins such as α-synuclein, parkin, PINK1, DJ-1, LRRK2 or UCHL1 have emerged into the research arena.31 However, very few of these models have yet been studied in relation to nociceptive changes and those that have display little in the way of changes. The gene discussed is PRKN; the disease is Parkinson disease.