Crohns and Arthritis

My nephew, who is 10, was diagnosed with Crohn's about 3 years ago.  I was originally diagnosed with psoriatric arthritis about 5 years ago, and that was changed to RA last December.  One question: is there a genetic link between the diseases we are experiencing?  He truly struggles with his disease, as pediatric Crohns seems to be non-existant as a researched entity, and I am concerned that as his life goes on other things may pop up, furthering his misery.
Also, is there any likelihood of my developing Crohns?  I am a 41 yo female with a hiatal hernia and peptic lesions.  I also suffer from chronic constipation.
Thank you!  

[Lisa Kessler, MS, CGC]

It is difficult to see family members struggle with medical problems, and I hope that this information can help you and your family.  Rheumatoid arthritis, psoriatic arthritis, and Crohn disease are all considered autoimmune diseases.  They are most likely caused by a combination of genes and environmental factors.  Several genes have been found that cause an increased risk to develop rheumatoid arthritis.  

Another gene named, CARD15 or NOD2, was demonstrated to be associated with both Crohn disease and with psoriatic arthritis.  Clinical genetic testing of the NOD2 gene is available.    

To learn more about the significance of your family history and if this type of testing would be of benefit to you, you and your family may want to meet with a genetic counselor.  In order to locate a genetic counselor in your area, please visit the National Society of Genetic Counselors (NSGC) website and click on “Find a Counselor”.    A genetic counselor can also review your family history in detail and help assess the risks of different family members of inheriting genetic conditions in the family.