The antiapoptotic role of HTT and the observation that mutant HTT induces apoptosis (Zeitlin et al., 1995; Cooper et al., 1998; Hackam et al., 1998; Lunkes and Mandel, 1998; Reddy et al., 1998; Hodgson et al., 1999; Dragatsis et al., 2000; Rigamonti et al., 2000; Leavitt et al., 2001) suggest that apoptosis may also be another common pathway shared in polyQ-related neurodegenerative diseases. The gene discussed is HTT; the disease is neurodegenerative disease.