CHOP plays an important role in ER stress-induced apoptosis (Wang et al., 1996; Zinszner et al., 1998; Maytin et al., 2001; McCullough et al., 2001; Oyadomari et al., 2001; Gotoh et al., 2002), and accumulated evidence also shows that CHOP-mediated apoptosis may also be involved in the development of Parkinson’s disease (Iadecola et al., 1997; Katayama et al., 1999; Sato et al., 2000). The gene discussed is DDIT3; the disease is Parkinson disease.