University of Helsinki - A Leading European University

News of the week

Week 34/2011: The genotype of multiple sclerosis is being revealed

The most extensive study ever conducted on the genetic background of multiple sclerosis has collected significant new information on the factors behind the disease. One of the research groups participating in the study published in the August issue of Nature was Professor Janna Saarela's group from Molecular Medicine Finland.

Multiple sclerosis is one of the most common neurological diseases affecting young adults, with approximately 2.5 million patients worldwide. It is an autoimmune disease, in which a chronic inflammation damages myelin which protects nerve cells and hinders the movement of impulses in the central nervous system.

The material of the genetic study conducted in fifteen countries comprised the DNA of approximately 10,000 MS patients and 17,000 control group members.

“The study found out that almost all the genes related to MS now recognised are also related to the immune defence system, and that approximately one-third of them have been perceived to increase the risk of other autoimmune diseases. It was also revealed that at least dozens of genetic variants affect the disease risk. Only some of these are known,” says Saarela, summing up the research results.

It is hoped that the study findings will shed light on the mechanism the body uses to attack the brains and spinal cord in multiple sclerosis. The more detailed knowledge of the hereditary mechanisms of the disease is also encouraging for the more accurate treatment of multiple sclerosis and other autoimmune diseases as well as early prevention related to environmental factors.

“The results improve our understanding on what happens when the body reacts wrongly and why this erroneous reaction is directed at different organs in different autoimmune diseases,” says Saarela.

It was known that many of the genes now linked with multiple sclerosis are central to the functioning of the immune system, so the study provides further proof of MS as a perturbation of the body’s immune system.

However, Saarela points out that the about fifty recognised gene variants are not enough to develop a gene test to detect multiple sclerosis.

“The variants thus far recognised explain only part of the heritability of multiple sclerosis. We need further study and recognition of functional gene variants increasing the actual disease risk.”

Professor Saarela’s research group participates in various international studies charting the genetic background of multiple sclerosis.

Text: Mikko Pelttari
Picture: Wikipedia
Translation: AAC Global

www.helsinki.fi/magazines »»
Research news archive »»