The research, published in Genome Research, found 2776 ‘binding sites’ where vitamin D attached to the genome, many of which were concentrated around genes that have been linked to autoimmune conditions such as multiple sclerosis and rheumatoid arthritis and diseases such as colorectal cancer and lymphocytic leukaemia.
The researchers said the findings backed the role of vitamin D in maintaining health in a world where one billion people are estimated to be vitamin D deficient due to either diet or lack of sunlight.
"There is now evidence supporting a role for vitamin D in susceptibility to a host of diseases,” said lead author Dr Sreeram Ramagopalan from the Wellcome Trust Centre for Human Genetics.
“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.”
The researchers isolated fragments of DNA bound to vitamin D receptors (VDRs), treated them with vitamin D form calcitrol, and then sequenced the DNA fragments.
VDRs are proteins activated by vitamin D that attach to DNA and influence which proteins are made from our genetic code.
In this way they identified the 2776 vitamin D binding sites, which Dr Ramagopalan said illustrated the importance of vitamin D in gene expression.
The research was funded by the Medical Research Council (MRC), the MS Society, the Wellcome Trust and the MS Society of Canada and conducted by the University of Oxford.
"Vitamin D status is potentially one of the most powerful selective pressures on the genome in relatively recent times.Our study appears to support this interpretation and it may be we have not had enough time to make all the adaptations we have needed to cope with our northern circumstances," said one of the authors, Professor George Ebers, from the Action Medical Research Professor of Clinical Neurology, in reference to skin shade and sunlight exposure ratios.
‘A ChIP-seq defined genome-wide map of vitamin D receptor binding: associations with disease and evolution’