Evidence
Genetic study shows direct link between vitamin D and MS susceptibility ‘gene’
Scientists have found evidence that a direct interaction between vitamin D and a common genetic variant alters the risk of developing multiple sclerosis (MS).
The research published in the journal PLoS Genetics suggests that vitamin D deficiency during pregnancy and the early years may increase the risk of the offspring developing MS later in life.
The causes of MS are unclear, but it has become evident that both environmental and genetic factors play a role. Previous studies have shown that populations from Northern Europe have an increased MS risk if they live in areas receiving less sunshine.
This supports a direct link between deficiency in vitamin D, produced in the body through the action of sunlight, and increased risk of developing the condition.
Now, in a study funded by the UK’s MS Society, the MS Society of Canada, the Wellcome Trust and the Medical Research Council, researchers at the University of Oxford and the University of British Columbia have established a direct relationship between a gene variant known as DRB1*1501 and vitamin D.
The research has been welcomed by Simon Gillespie, Chief Executive of the MS Society (UK).
“These remarkable results tie together leading theories about the environment, genes and MS but they are only part of the jigsaw,” he said. “This discovery opens up new avenues of MS research and future experiments will help put the pieces together.”
While one in 1,000 people in the UK are likely to develop MS, this number rises to around one in 300 amongst those carrying a single copy of the variant and one in 100 of those carrying two copies.
The researchers found that proteins activated by vitamin D in the body bind to a particular DNA sequence lying next to the DRB1*1501 variant, in effect switching the gene on.
“In people with the DRB1 variant associated with MS, it seems that vitamin D may play a critical role,” said co-author Dr Julian Knight. “If too little of the vitamin is available, the gene may not function properly.”
“We have known for a long time that genes and environment determine MS risk,” said Professor George Ebers, University of Oxford. “Here we show that the main environmental risk candidate – vitamin D – and the main gene region are directly linked and interact.”
“Our study implies that taking vitamin D supplements during pregnancy and the early years may reduce the risk of a child developing MS in later life,” said lead author Dr Sreeram Ramagopalan.
“Vitamin D is a safe and relatively cheap supplement with substantial potential health benefits. There is accumulating evidence that it can reduce the risk of developing cancer and offer protection from other autoimmune diseases.”
