Breakthrough Research Holds Clues About MS Cause

In one of the largest human genetic studies ever undertaken, scientists have identified the major common genetic variants that contribute to the cause of the devastating neurologic disease, multiple sclerosis (MS).

The results of the study are published today in the prestigious scientific journal, Nature. They represent years of work by the International Multiple Sclerosis Genetics Consortium (IMSGC) involving more than 250 researchers in 15 countries.

University of Otago, Christchurch, researchers were involved in the study and more than 1000 New Zealanders contributed samples.

The study confirmed the presence of up to 57 MS genes with a remarkable pattern that shows that the reason some people get MS and others don’t is largely due to subtle, inherited differences in immune function. It points to a pivotal role for T cells – the ‘orchestra leaders’ of the immune system and makes it clear that MS is primarily an immunologic disease.

The New Zealand contribution was led by Professor Bruce Taylor, now based in Tasmania and Dr Deborah Mason, a clinical senior lecturer at the University of Otago, Christchurch and consultant neurologist at Canterbury District Health Board.

In 2006 Drs Taylor, Mason and colleagues from the University of Otago, and the University of Canterbury, conducted the first ever national prevalence study of MS.

Dr Mason says in 2007, as part of an ongoing collaboration with other MS researchers the Australia and New Zealand Multiple Sclerosis Genetics Consortium (ANZgene) was formed.

ANZgene researchers identified two new genetic areas or loci which conferred susceptibility to MS. This study was published in Nature Genetics in 2009 (2) and lead to its involvement with the Wellcome Trust Case Control Consortium and The International Multiple Sclerosis Genetics Consortium (IMSGC).

Dr Mason says one of the ongoing controversies in MS is whether damage to the nervous system is primarily a degenerative process or whether it results from inflammation mediated by the immune system. The study published today in Nature strongly supports the later and confirms a pivotal role of the immune system.

“Whilst we still do not understand what causes or triggers the immune dysfunction, widely believed to be an environmental trigger, this study increases our understanding of the immune mechanisms which contribute to damage. In addition the study also confirms a possible link between MS and a proposed environmental factor, Vitamin D metabolism,’’ Dr Mason says.

The Australian contribution was led by Professor Graeme Stewart, a Clinical Immunologist in the Westmead Millennium Institute, University of Sydney.

“Discovering so many new leads is an enormous step towards understanding the cause of MS,” Professor Stewart says. “Most importantly, for people with MS, these genes also strengthen the case for immunologic treatments currently in clinical trials and point to new therapeutic approaches.”