Monoclonal gammopathy of unknown significance, or MGUS, refers to an asymptomatic blood disorder characterized by the presence of monoclonal protein, or M protein, in the blood, according to Mayo Clinic. The protein is produced by a type of white blood cell in the bone marrow known as a plasma cell.
Causes of monoclonal gammopathy of unknown significance are unknown although genetics and the environment seem to contribute to the disorder, explains Mayo Clinic. Since the condition does not have any symptoms besides the rare tingling in some sufferers, its detection is usually accidental through routine blood tests for other conditions. Once the condition is detected, doctors use the serum protein electrophoresis, or SPE, and the free light chain assay tests to check for abnormal proteins or get a closer look at the structure of the M protein.
MGUS is a benign condition that does not require treatment. However, research indicates it is a predisposing risk factor to other blood plasma disorders such as multiple myeloma, states the National Cancer Institute. Although a big percentage of people with MGUS do not go on to contract multiple myeloma, those found with multiple myeloma all have a pre-existing MGUS condition. Thus, it is important for all MGUS sufferers to get lifelong checkups to monitor their protein levels and check for the development of any new symptoms.