HLA-B42

HLA-B42 is a human leukocyte antigen (HLA) serotype. The HLA system is a group of genes that are important in the immune system's ability to recognize and respond to foreign substances. HLA-B42 is part of the HLA-B locus, which is a subcategory of the larger HLA system.

Function

HLA-B42, like other HLA types, plays a crucial role in the immune system's ability to recognize and respond to foreign substances. It does this by presenting peptides (small pieces of proteins) from inside the cell to the immune system. If these peptides are foreign (for example, from a virus or bacteria), the immune system will mount a response against them.

Genetics

HLA-B42 is encoded by the HLA-B*42 allele. This allele is part of the larger HLA-B locus, which is located on the short arm of chromosome 6 (6p21.3). The HLA-B locus is highly polymorphic, meaning that there are many different versions (alleles) of the genes in this locus in the human population.

Clinical significance

HLA-B42 has been associated with a number of diseases. For example, it has been linked to an increased risk of rheumatoid arthritis, a chronic inflammatory disorder affecting many joints, including those in the hands and feet. It has also been associated with a decreased risk of celiac disease, an immune reaction to eating gluten, a protein found in wheat, barley, and rye.

See also

• HLA-B
• Human leukocyte antigen
• Immune system
• Rheumatoid arthritis
• Celiac disease