Figure 19-19 shows the association mapping, which was used to identify genes for disease susceptibility. HLA-DRB1 gene shows significant P values for rheumatoid arthritis and type 1diabetes.
Both these diseases are classified as autoimmune diseases that results from inappropriate immune response of the body.
HLA gene is one of the major histocompatibility complex (MHC) genes in all vertebrates. These are the genes, which determine the susceptibility to an autoimmune disease and regulate the immune response of the body.
Mutations in these genes results in abnormal immune responses, which is the cause of these two diseases.