Distribution of HLA-DQB1 in Czech Patients with Central Hypersomnias.

The aim of our study was to analyze the distribution of HLA-DQB1 in Czech patients with central hypersomnias and differences between diagnostic groups of narcolepsy type 1 (NT1), type 2 (NT2), idiopathic hypersomnia (IH) and no central hypersomnia subjects (no-CH). Statistical analysis of DQB1 genotyping was performed on the cohort of 716 patients (375 men, 341 women) with reported excessive daytime sleepiness. DQB106:02 allele was present in 94% of the NT1 patients. The decrease of DQB106:03 allele was also confirmed. No other DQB106 allele nor any other DQB1 allele group was differently distributed in the NT1. In the cohort of NT2 patients DQB106:02 allele was present in 43%. Allele group DQB05 was detected with a significantly higher frequency in this diagnostic unit. Any differences in presence of DQB105 alleles in NT2 patients were not reported so far. The cohort of patients with IH did not show any difference in allele distribution of DQB1 alleles/allele groups comparing to healthy controls. DQB106:02 allele was significantly increased in the no hypersomnia group. No other DQB1 allele/allele group had any difference in distribution in patients comparing to healthy controls. The different distribution of DQB106:02 and other DQB1 alleles/allele groups was detected in analyzed diagnostic groups. These results indicate that DQB1 contributes to the genetic predisposition to NT1, NT2, IH and no-CH in different manners.