HLA-DQB2

HLA-DQB2 is a human leukocyte antigen (HLA) gene located on chromosome 6p21.32. Specifically, it encodes the beta chain of the HLA-DQ heterodimer. HLA-DQ is a cell surface receptor protein crucial for the adaptive immune system's function. It belongs to the major histocompatibility complex (MHC) class II family.

The HLA-DQ heterodimer is formed by an alpha chain encoded by an HLA-DQA gene (such as HLA-DQA1) and a beta chain encoded by an HLA-DQB gene, such as HLA-DQB2. This heterodimer presents processed peptide antigens to T helper cells, initiating an immune response.

HLA-DQB2 is highly polymorphic, meaning it exists in many different allelic variants. These variations affect the peptide-binding groove of the HLA-DQ molecule, influencing which peptides can be presented to T cells. Consequently, different HLA-DQB2 alleles are associated with varying susceptibilities to autoimmune diseases, such as type 1 diabetes and celiac disease, and other immune-related disorders.

The specific role of HLA-DQB2 in disease susceptibility is complex and often involves interaction with other HLA genes. For example, certain combinations of HLA-DQA and HLA-DQB alleles can create particularly strong associations with autoimmune conditions. Understanding the specific HLA-DQB2 allele and its interaction with other HLA genes is critical for assessing individual risk and developing targeted therapies for these diseases. The presence or absence of specific HLA-DQB2 alleles can also be used as a diagnostic marker in some contexts.