FCGR2A gene

The FCGR2A gene (FCGR2A stands for: Fc gamma receptor IIa) is a protein-coding gene located on chromosome 1q23.3. The encoded receptor protein of the same name binds with low affinity to the Fc region of immunoglobulins gamma. By binding to IgG, it initiates cellular immune responses against pathogens and soluble antigens. Promotes phagocytosis of opsonized antigens. The Gene Ontology (GO) essentially describes the binding of IgG. An important paralog of this gene is FCGR2C .

The FCGR2A gene encodes a member of a family of immunoglobulin Fc receptor genes found on the surface of many immune cells (see CD30 below). The protein encoded by this gene is a cell surface receptor that is localized on phagocytic cells such as macrophages and neutrophils and is involved in phagocytosis and the removal of immune complexes. Alternative splicing leads to multiple transcript variants. [provided by RefSeq, Oct. 2008]

Diseases associated with FCGR2A include cystic fibrosis and systemic lupus erythematosus. FCGR2A polymorphisms are associated with an increased risk of idiopathic (immune) thrombocytopenic purpura. Associated signaling pathways include ADORA2B-mediated production of anti-inflammatory cytokines and the innate immune system (Ou Y et al. 2020; Xu J et al. 2016).

In a Korean patient cohort, FCGR2A was specifically associated with male patients (<1 year) suffering from mucocutaneous lymph node syndrome (M.Kawasaki). (Sim BK et al. 2019).

1. Ou Y et al. (2020) Relationship between the IL-10 (-1082 A/G) polymorphism and the risk of immune/idiopathic thrombocytopenic purpura: A meta-analysis. Cytokine 125:154820.
2. Sim BK et al. (2019) Assessment of the Clinical Heterogeneity of Kawasaki Disease Using Genetic Variants of BLK and FCGR2A. Korean Circ J 49:99-108.
3. Xu J et al. (2016) CD16 and CD32 Gene Polymorphisms May Contribute to Risk of Idiopathic Thrombocytopenic Purpura. Med Sci Monit 22:2086-2096.
4. Wang D et al. (2014) FCGR2A rs1801274 polymorphism is associated with risk of childhood-onset idiopathic (immune) thrombocytopenic purpura: evidence from a meta-analysis. Thromb Res134(6):1323-1327.