FcεRIα produces beneficial effects in defense and immunopathology against several types of parasite infections, including Schistosoma mansoni (24) and Haemaphysalis longicornis ticks (25, 26), etc. Lack of FcεRIα causes increased skin penetration by ticks and worsened liver pathologies in animals infected with S. mansoni. The gene discussed is FCER1A; the disease is infection.