Most narcolepsy patients also suffer from cataplexy, a sudden reduction or loss of muscular tone not accompanied by loss of consciousness caused by the loss of hypocretin-1 (orexin) producing neurons in the lateral hypothalamus (Lin et al., 1999; Thannickal et al., 2000; Nishino et al., 2010). This evidence concerns the gene HCRT and narcolepsy.