Reiter’s syndrome (reactive arthritis) is a form of arthritis first discovered by Hans Reiter, a physician in the German army during the World War II.  He described the classical symptoms of the disorder that as arthritis, redness of the eyes, and urinary tract signs. Further investigations and research led the doctors to believe that Reiter’s syndrome (reactive arthritis) is a seronegative spondyloarthropathic disease for and it is one of those peculiar disorders that cause irritation and soreness all over the body. The typical areas of the body particularly affected by this disease are the parts of the spine the joints where tendons attach to bones.

Reiter’s syndrome is also known as reactive arthritis, since the arthritis is more of a ‘reaction’ to infections that affect some other part of the body. In case of many patients, this infection is genitourinary in nature i.e. the bladder, urethra, penis or the vagina may have developed some signs of an infection. Such an infection is most commonly transmitted from one person to another by sexual intercourse and is referred to as genitourinary or urogenital Reiter’s syndrome. Another form of the same disorder is known as enteric or gastrointestinal Reiter’s syndrome (reactive arthritis). This develops when a person eats food preparations that are contaminated with bacteria. However, the presence of infectious disease in the body is alone not enough for a person to develop Reiter’s syndrome. A genetic factor, HLA-B27, is identified in patients who have been affected with this disease. About 80 percent of people suffering from Reiter’s syndrome are reported to be HLA-B27 positive. Thus, a combination of environmental and genetic factors triggers the development of reactive arthritis.

Even though HLA-B27 is strongly related to the susceptibility to the Reiter’s syndrome , new studies have thrown light on the presence of an additional susceptibility or modifying gene that acts in association with the HLA-B27 to add to the disease pathogenesis. These genes have been called as TAP genes (transporters associated with antigen processing) and have the potential to contribute to the progression o the disease because they are polymorphic. Their main function is to transport antigenic peptides that are usually found in HLA class I molecules. The presence of TAP1 and TAP2 alleles was tested in the case of 34 patients who had Reiter’s Syndrome(reactive arthritis). Out of the 34 patients, 28 were HLA-B27 positive while six were HLA-B27 negative. The results showed that the allele frequency of TAP1C and TAP2A was greater in patients with Reiter’s syndrome and who had tested positive for the HLA-B27 gene. The connection observed linking TAP alleles and the presence of Reiter’s Syndrome is not dependent on the existence of HLA-B27, and regardless of the physical propinquity of HLA class II and TAP genes. Consequently, TAP genes are genetically divided, but functionally linked to class I genes, and both add to vulnerability to Reiter’s syndrome.