ALT In our recently published study, we examined various diseases, in total about 500, to identify their similarities and differences, without focusing on the traditional way of grouping them by organ systems. We discovered several interesting connections, some of which were already known. For example, we found that psoriasis is closely related to Crohn's disease, ulcerative colitis, rheumatoid arthritis, and other autoimmune and inflammatory diseases, but it is less similar to other skin conditions.