The SAA1 gene provides instructions for making a protein called serum amyloid A1. This protein is made primarily in the liver and circulates in low levels in the blood. Although its function is not fully understood, serum amyloid A1 appears to play a role in the immune system. Serum amyloid A1 may help repair damaged tissues, act as an antibacterial agent, and signal the migration of germ-fighting cells to sites of infection.
Levels of this protein increase in the blood and other tissues under conditions 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 has been accomplished, the body stops the inflammatory response to prevent damage to its own cells and tissues.
There are three versions of the serum amyloid A1 protein, known as alpha, beta, and gamma, which differ by one or two protein building blocks (amino acids). The frequency of these versions differs across populations. In white populations, for example, the alpha version predominates and gamma is rare. In the Japanese population, however, the three versions appear almost equally.
Other Names
PIG4; SAA; SAA_HUMAN; TP53I4; tumor protein p53 inducible protein 4
Related Genetics Topics
Identifiers
- NCBI Gene: 6288
- OMIM: 104750
Source: MedlinePlus Genetics, U.S. National Library of Medicine.
