Deposits of amyloid peptides and proteins such as amyloid β-protein (Aβ), islet amyloid polypeptide (IAPP or amylin) and semen-derived enhancer of viral infection (SEVI) are involved in a variety of human diseases, including Alzheimer, Parkinson, Huntington and Creutzfeld-Jakob diseases, type II diabetes or HIV infection. The gene discussed is IAPP; the disease is viral infectious disease.