Huntington's disease is characterised by unwanted movements, psychiatric disturbances and cognitive decline. Less well recognised symptoms and signs are weight loss, autonomic dysfunction and sleep disorders. In this study we focus on hypocretin-1 and hypothalamus functions. We found a reduction by about 30% in hypocretin signalling in patients with HD. However, it remains unclear whether this moderate decrease in hypocretin signalling contributes to clinical symptoms.