Vitamin D deficiency linked to wide array of diseases

WASHINGTON - Researchers have mapped the points at which vitamin D interacts with our DNA - and identified over two hundred genes that it directly influences.

The study highlights the extent to which vitamin D deficiency may increase susceptibility to a wide range of diseases.

Now, researchers at the University of Oxford have shown the extent to which vitamin D interacts with our DNA. They used new DNA sequencing technology to create a map of vitamin D receptor binding across the genome. The vitamin D receptor is a protein activated by vitamin D, which attaches itself to DNA and thus influences what proteins are made from our genetic code.

The researchers found 2,776 binding sites for the vitamin D receptor along the length of the genome. These were unusually concentrated near a number of genes associated with susceptibility to autoimmune conditions such as MS, Crohn’s disease, systemic lupus erythematosus (or ‘lupus’) and rheumatoid arthritis, and to cancers such as chronic lymphocytic leukaemia and colorectal cancer.

They also showed that vitamin D had a significant effect on the activity of 229 genes including IRF8, previously associated with MS, and PTPN2, associated with Crohn’s disease and type 1 diabetes.

“Our study shows quite dramatically the wide-ranging influence that vitamin D exerts over our health,” said Dr Andreas Heger from the MRC Functional Genomics Unit at Oxford, one of the lead authors of the study.

“There is now evidence supporting a role for vitamin D in susceptibility to a host of diseases. Vitamin D supplements during pregnancy and the early years could have a beneficial effect on a child’s health in later life. Some countries such as France have instituted this as a routine public health measure,” added the first author of the paper, Dr Sreeram Ramagopalan from the Wellcome Trust Centre for Human Genetics.

The main source of vitamin D in the body comes from exposing the skin to sunlight, although a diet of oily fish can provide some of the vitamin.

A lack of vitamin D can affect bone development, leading to rickets; in pregnant mothers, poor bone health can be fatal to both mother and child at birth, hence there are selective pressures in favour of people who are able to produce adequate vitamin D.

The results are published today in the journal Genome Research. (ANI)