The disruption of self-tolerance during the development of autoimmunity is a critical factor. Although our understanding of immune regulation is improving, the mechanisms that lead to this loss in many autoimmune diseases remain elusive. Autoimmunity generally emerges when people with genetic risk are exposed to environmental factors. Recent studies highlight the significance of the interaction between genetic factors and epigenetic changes resulting from environmental influences, which might play a major role in the onset of these conditions. Research efforts are identifying genetic loci associated with autoimmunity, resulting in a rapid increase in the number of recognized related genes. Furthermore, there is growing evidence that environmental factors like stress, toxins, lifestyle, etc., can alter gene expression through epigenetic mechanisms. This article presents an extensive overview of the current knowledge regarding the genetics and epigenetics of autoimmune disorders like multiple sclerosis (MS), rheumatoid arthritis (RA), and type 1 diabetes (T1DM). By examining these connections, we hope to uncover insights that could enhance prevention and treatment strategies for autoimmune disorders.