A collection of reagents and other associated materials intended to be used for the qualitative and/or quantitative detection of nucleic acid from one or multiple HLA class II antigens in a clinical specimen, using a nucleic acid technique (NAT). It may be used to detect specific HLA gene alleles associated with an inborn/inherited genetic disorder or a predisposition to develop an autoimmune disease (e.g., type 1 diabetes mellitus, Coeliac disease, narcolepsy, Crohn’s disease, inflammatory bowel disease (IBD), psoriasis and rheumatoid arthritis). It may also be used for selecting treatment options for immunotherapy.