Gene HLA-DQB1
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Also known as
major histocompatibility complex class II DQ beta 1, HLA-DQB, MHC class II DQ beta chainOverview
HLA-DQB1 (HLA Class II Histocompatibility Antigen DQ Beta 1) encodes the beta chain of the HLA-DQ heterodimer, critical for antigen presentation to CD4+ T cells. The HLA-DQ molecule formed with HLA-DQA1 determines which peptides can be presented to the immune system. HLA-DQB1 is one of the most disease-associated HLA genes, with variants linked to multiple autoimmune conditions.The DQB1*02:01 allele (encoding DQ2) and DQB1*03:02 allele (encoding DQ8) are essential for celiac disease development, conferring approximately 40-fold increased risk. These alleles are also associated with type 1 diabetes, though different HLA-DQ variants may confer risk or protection. HLA-DQB1 variants additionally influence susceptibility to narcolepsy, with DQB1*06:02 present in over 90% of narcolepsy with cataplexy cases.
Understanding your HLA-DQB1 genetic status provides important information about autoimmune disease susceptibility. Testing for celiac-associated HLA-DQ types has become a standard component of celiac disease workup, with essentially 100% negative predictive value when both DQ2 and DQ8 are absent.