Researchers have uncovered new evidence of a genetic link between vitamin D deficiency and increased risk of multiple sclerosis (MS).
Multiple sclerosis is a complex and progressive inflammatory disease of the central nervous system typically diagnosed in young adulthood. The disease is known to have genetic and environmental links, and the marked geographical distribution of cases, which increase significantly the further north populations are located, led to vitamin D being investigated as a potential key risk factor. Potential genetic interactions involved in this mechanism have already been identified (see previous news).
Now, scientists from Canada and the UK have identified a rare genetic mutation in 3000 adults with MS and their unaffected parents. A copy of a rare variant of the CYP27B1 gene was present in 35 affected adults, all of whom had inherited it form a parent. This variant was found to be independently associated with an inherited form of vitamin D deficiency.
The researchers say that these findings further strengthen evidence of the importance of vitamin D deficiency in MS and may justify large-scale trials of vitamin D supplementation as a preventative strategy in northern countries such as Scotland with the highest incidence of the disease.
Comment: Although lack of vitamin D is clearly not the sole cause of this complex disease, the evidence provided by genetic studies is proving highly valuable in offering a potential new way of reducing the number of people affected by MS; vitamin D supplementation is a relatively cheap and low-risk intervention that could be implemented at the population level.