Narcolepsy

HLA-DQB1*06:02

Narcolepsy with cataplexy (type 1) arises from the loss of hypocretin-producing nerve cells in the brain, presumably autoimmune. It is exceptionally tightly bound to HLA-DQB1*06:02: nearly all patients carry this type, while it is common and harmless in the general population.

A very tight but unspecific link

Hardly any disease is as strongly bound to an HLA allele as narcolepsy type 1 is to DQB1*06:02. Because this type occurs in about a quarter of all people, however, its presence proves nothing. Its absence, by contrast, makes narcolepsy type 1 very unlikely.

Context

The diagnosis rests on clinical findings, sleep laboratory and, where appropriate, the hypocretin level in cerebrospinal fluid. Genome shows only the HLA type as technical evidence, without diagnostic claim.

What Genome measures. Whether HLA-DQB1*06:02 is present in the HLA typing, as a nearly necessary but far from sufficient context marker.

Related topics

HLA and autoimmunityHLA typing

Sources

  1. 1Tafti et al., 2014 DQB1 locus alone explains most of the risk and protection in narcolepsy with cataplexy in Europe. Sleep 37:19–25. doi.org/10.5665/sleep.3300
  2. 2Liblau et al., 2015 Hypocretin (orexin) biology and the pathophysiology of narcolepsy with cataplexy. The Lancet Neurology 14:318–328. doi.org/10.1016/S1474-4422(14)70218-2