Polymorphisms in the vicinity of the hypocretin/orexin are not associated with human narcolepsy

Human narcolepsy/cataplexy is associated with reduced hypocretin (orexin) t ransmission. A common preprophypocretin (HCRT) polymorphism (-909C/T) was i dentified and tested in 502 subjects (105 trio families, 80 Caucasian narco lepsy cases, and 107 Caucasian control subjects). This polymorphism was not associated with the disease. The promoter and 5' untranslated (5'URT) regi ons of the HCRT gene (-320 to +21 from ATG) were also sequenced in 281 subj ects. None of the subjects carried -22T, a rare 5'UTR polymorphism previous ly reported to be associated with narcolepsy. The HCRT locus is not a major narcolepsy susceptibility locus.