FCER1A (High Affinity Immunoglobulin E Receptor Subunit Alpha) is a gene that encodes a protein crucial for allergic reactions. It binds to immunoglobulin E (IgE) and activates mast cells and basophils, leading to the release of histamine and other inflammatory mediators. This process plays a role in allergy and asthma symptoms, making FCER1A an important target for therapies designed to reduce allergic responses.