Grüter et al. identified that HLA-DRB1*10:01- and HLA-DQB1*05:01-positive patients were significantly younger at disease onset, more frequently exhibited characteristic sleep disorders, and had a higher IgLON5-IgG titre compared to HLA-DRB1*non-10:01 and HLA-DQB1*non-05:01 patients [8]. Here, HLA-DRB1 is linked to sleep disorder.