Autoimmune Disease Clusters and Crohn's

Happy Holidays! Saw this article (GWAS Meta-Analysis Supports Existence of Autoimmune Disease Clusters) today about a study conducted by Stanford University researchers. They were trying to see if there were any connections between different auto-immune diseases. Specifically, they looked at six autoimmune diseases - type 1 diabetes, rheumatoid arthritis, Crohn's disease, multiple sclerosis, autoimmune thyroid disease, and ankylosing spondylitis - and five non-autoimmune diseases to see if genetic factors related these diseases with each other.

The researchers did find that diseases go together. However, Crohn's is not related to any of these other diseases. Here's the excerpt:

Based on their analyses, the researchers suggest autoimmune diseases fall into at least two different groups: one containing rheumatoid arthritis and ankylosing spondylitis and another containing multiple sclerosis and autoimmune thyroid disease.

Meanwhile, they reported, type 1 diabetes resembled both of the groups to a certain extent, sharing characteristics with autoimmune thyroid disease but not multiple sclerosis. Crohn's disease, on the other hand, did not cluster with either group.

I suppose we're just in a category of our own =)