This application discloses methods, systems and kits for correlating the presence or absence of certain nucleic acid sequences within a population with the ability to create immune tolerance in that same population. Tolerance can be induced by solo or repeated administration of antigen, including soluble antigens administered either intravenously or sublingually. This application also discloses methods for detecting variants. In addition the application addresses the use or avoidance of non steroidal anti inflammatory drugs in therapy.