The protein encoded by FCGR3B is a low affinity receptor for the Fc region of gamma immunoglobulins (IgG). The encoded protein acts as a monomer and can bind either monomeric or aggregated IgG. FCGR3B may function to capture immune complexes in the peripheral circulation. Several transcript variants encoding different isoforms have been found for FCGR3B. A highly-similar gene encoding a related protein is also found on chromosome 1.
