Immune fault 'link' to narcolepsy

Scientists at Stanford University research appears in the journal Nature Genetics have uncovered genetic evidence suggesting the sleep disorder narcolepsy is linked to a fault in the immune system's T-cells,they attack the cells in the sleep centres of the brain.

• Narcolepsy, which causes extreme daytime sleepiness and sudden muscle weakness, has previously been linked to a malfunctioning immune system. It can trigger "sleep attacks" without any warning during any normal activity.
• In addition, some people can experience "cataplexy", where strong emotions such as anger, surprise, or laughter can trigger an instant loss of muscle strength, which, in some cases, can cause collapse.
• There is currently no cure for narcolepsy, only ways to minimise symptoms such as taking frequent, brief naps evenly spaced throughout the day.

• They pinpointed three specific genetic variants in the same gene in people with European and Asian ancestry that appeared to be associated with an increased susceptibility for narcolepsy.The gene in question plays a key role in the functioning of an important receptor used by T-cells to recognise foreign proteins in the body.

• Dr Mignot said: "Narcolepsy is probably the result of a series of unfortunate events, starting with genetic predisposition, involvement of an environmental trigger such as an infection, then T-cell activation, then effects on many other arms of the immune system."

• He said the latest study raised the possibility of developing a therapy for narcolepsy which worked by blocking activity of the specific T-cell receptors.
• Identifying the genetic variants may also provide a diagnostic tool to pick up narcolepsy at an early stage.
• Dr Mignot added: "I believe that narcolepsy could be a very interesting model for studying autoimmune diseases that affect the brain.