HCRT and Alzheimer disease: Findings indicating higher incidence of AD in females [53], worse cognitive performance in female mice in a transgene mice model of dementia [54], pronounced impairment of sleep in females [55], the modulation of HCRT-receptor-1 by gonadal steroids [56] and a sexually dimorphic expression of HCRT-1 [57] make further investigation of a gender dependence of HCRT-1 regulation in AD warranted.