What are the genetic changes related to familial Mediterranean fever ?
Mutations in the MEFV gene cause familial Mediterranean fever. The MEFV gene provides instructions for making a protein called pyrin (also known as marenostrin), which is found in white blood cells. This protein is involved in the immune system, helping to regulate the process of inflammation. Inflammation occurs when the immune system sends signaling molecules and white blood cells to a site of injury or disease to fight microbial invaders and facilitate tissue repair. When this process is complete, the body stops the inflammatory response to prevent damage to its own cells and tissues.  Mutations in the MEFV gene reduce the activity of the pyrin protein, which disrupts control of the inflammation process. An inappropriate or prolonged inflammatory response can result, leading to fever and pain in the abdomen, chest, or joints.  Normal variations in the SAA1 gene may modify the course of familial Mediterranean fever. Some evidence suggests that a particular version of the SAA1 gene (called the alpha variant) increases the risk of amyloidosis among people with familial Mediterranean fever.