Jan 31, 2014

Discovery of Genetic Markers Leads to Personalized Treatment of Patients with Autoimmune Diseases

By Suniya Kukaswadia

A Faculty of Medicine researcher has discovered genetic markers that could change the way physicians diagnose autoimmune diseases, leading to more targeted and personalized care.Professor Katherine Siminovitch (Department of Medicine) and a team of international scientists uncovered 40 new genetic markers for rheumatoid arthritis, an inflammatory disease that affects one per cent of the world’s population.

The team also discovered an overlap between the genetic markets for rheumatoid arthritis and markers for other autoimmune diseases such as Type 1 Diabetes, Lupus and certain cancersScientists have only begun to uncover the causes of autoimmune diseases such as rheumatoid arthritis, but understand that both genetic factors and environmental triggers play a role. The causes of autoimmune diseases such as rheumatoid arthritis have previously been unknown, but both genetic factors and environmental triggers play a role. The triggers are hard to pinpoint because they may occur years before the patient shows symptoms. The key, according to Siminovitch, is to find the genetic pathways that predispose to these diseases in order to understand why certain people are susceptible, what outcome each affected person will experience, and how each patient will respond to specific medications.

“We can now determine the genetic pathways that lead to rheumatoid arthritis in individual patients. We hope to use this information in the clinic by selecting each patient’s treatment based on cause rather than by trial-and-error,” says Siminovitch, who is Director of the Office of Personalized Genomics and Innovative Medicine at Mount Sinai Hospital. Genetic information may also soon allow physicians to proactively identify and treat those who are at a high risk for rheumatoid arthritis.

“New genetic information has revealed many overlaps in the cell pathways leading to one autoimmune disease versus another. Because many of the drugs we use to treat autoimmune diseases target specific pathways, these overlaps imply that a treatment working in one autoimmune disease may also be valuable in treating another. For example, a drug used to treat rheumatoid arthritis may be effective in treating patients with inflammatory bowel disease if these diseases are caused by similar pathways. It’s a whole new ball game in terms of diagnosing and treating patients,” says Siminovitch.

There is currently no cure for rheumatoid arthritis, and at least half of all patients do not fully respond to the available treatments. The progression of the disease varies from case to case, but almost 50 per cent of all adults with the autoimmune disease are unable to work full time within 10 years of diagnosis.

Siminovitch’s work offers hope to patients world-wide. “In the next 10 years I would like to see remarkable new gains in genetic knowledge translate into ability to reduce risk for rheumatoid arthritis and other autoimmune diseases or at least to minimize progression of such diseases and achieve better outcomes.”