Gene:
complement component (3b/4b) receptor 1, including Knops blood group system
Gene ID:
191655
Symbol:
CR1
Species:
1000
Description:
This gene encodes a membrane glycoprotein found on peripheral blood cells, glomerular podocytes, and follicular dendritic cells. The protein is a receptor for complement components C3b and C4b and regulates the activity of the complement cascade. Variation in this protein is the basis of the Knops blood group system. The two most common alleles, F and S, differ by 8 exons and are thought to be the result of an unequal crossover event. A secreted form of the protein present in plasma has been described, but its full length nature has not been determined.