HCRT and narcolepsy: In addition, studies have found that individuals carrying HLA-DQB1*06:02 have a much greater risk of developing the disease than do noncarriers.[14] The presence of streptococcal infection may initiate or catalyze an autoimmune response against hypocretin cells in narcolepsy.[15] H1N1 influenza and related Pandemrix vaccinations have been suggested as possible specific environmental triggers for narcolepsy episodes.[16,17] It can be seen that genetic susceptibility, immune response, and environmental factors are all related to the pathogenesis of the disease.