HLA-DRB1*03:01 is associated with female sex and younger age of anti-LGI1 encephalitis.

The strong association between anti-LGI1 encephalitis and certain HLA class II alleles supports a primary autoimmune origin for the disease. Carriers of the DRB1*03:01 allele in Chinese patients with anti-LGI1 encephalitis are more likely to be female, to suffer earlier disease onset, and to respond better to immunotherapy.