Scientists discover influence of vitamin D in genes linked with autoimmune diseases

Vitamin D found to influence more than 200 genes, including some linked to cancer

UK scientists at the University of Oxford have discovered that vitamin D can affect the activity of more than 200 genes of cells grown in the lab. Some of these genes are known from previous studies to be involved in diseases like diabetes and cancer.

Using state-of-the-art DNA sequencing technology, the research team created a map of sites where the vitamin D receptor - a protein activated by vitamin D - attaches itself to DNA and activates particular genes.

Their map, which is detailed in the journal Genome Research, revealed 2,776 binding sites for the vitamin D receptor along the human genome.

These binding sites tended to be highly concentrated near a number of genes associated with susceptibility to autoimmune diseases - including multiple sclerosis and rheumatoid arthritis - and with certain cancers, such as chronic lymphocytic leukaemia and bowel cancer.

The researchers also showed that the vitamin had a significant effect on the activity of 299 genes, some of which have previously been linked to autoimmune diseases, in which the body's immune system starts to attack healthy tissue.

First author Dr Sreeram Ramagopalan, from the Wellcome Trust Centre for Human Genetics, commented: "There is now evidence supporting a role for vitamin D in susceptibility to a host of diseases."

However a Cancer Research UK spokesperson urged caution over interpreting the results, especially given that the evidence around vitamin D and cancer was still emerging.

Hazel Nunn, health information manager at Cancer Research UK, commented: "We know that vitamin D is essential for good bone health and while many studies have found a link with bowel cancer, we still can't be sure if vitamin D directly protects against this disease. This study adds to the evidence for vitamin D protecting against bowel cancer as well as many other diseases. We still need clinical trials to tell us if boosting levels of this important vitamin could help to prevent these conditions."

Ms Nunn advised: "The best way to get enough vitamin D is to enjoy the sun safely, taking care not to burn so as not to raise the risk of skin cancer. Eating plenty of oily fish as part of a healthy, balanced diet can help to maintain sufficient levels of vitamin D, particularly in people who don't get much sunlight. Anyone concerned they lack vitamin D should discuss taking supplements with their doctor."