IL4 and rheumatoid arthritis: The aim of this study was to determine if there was a link between IL-17, IL-4, IL-6, and IL-12 gene polymorphisms and rheumatoid arthritis disease susceptibility and severity in the Bangladeshi population, which might help in understanding whether these cytokine polymorphisms act as risk factors for the Bangladeshi rheumatoid arthritis population and may help in future treatment development.