Summary
Researchers at Oxford University identified that a gene that causes vitamin D deficiency may also cause MS. Growing evidence suggests that there is a link between vitamin D and MS. Subsequent studies have established that the closer people live to the equator the lower the risk of developing MS, and sunlight is strongly implicated as a cause. [Sreeram V Ramagopalan D.Phil, David A Dyment MD, D.Phil, M Zameel Cader MD, D.Phil, Katie M Morrison MSc, Giulio Disanto MD, Julia M Morahan PhD, Antonio J Berlanga-Taylor MD, Adam Handel MD, Gabriele C De Luca MD, D.Phil, A Dessa Sadovnick PhD, Pierre Lepage PhD, Alexandre Montpetit PhD, George C Ebers MD, FRCP, FmedSci. Epub ahead of print. Annals of Neurology. DOI: 10.1002/ana.22678]
Details
The DNA of 43 individuals with MS from families with 4 or more affected individuals was analyzed. It was noted that these individuals have a rare mutation in the CY27B1 gene. Further analysis of the DNA database from the Canadian Collaborative Project on the Genetic Susceptibility to Multiple Sclerosis (CCPGSMS) found that parents who had the mutated gene, transmitted it to their children.
It is known that two copies of this mutation results in vitamin D dependent rickets (which can lead to the softening and weakening of bones), while one copy of the mutation results in lower levels of calcitriol (a hormonally active form of vitamin D). Substantial association with the single copy mutation was found with the double copy mutation in 3,046 parent-child trios with MS. After determining the differences in the genetic make-up of 12,500 individuals, it was further discovered that additional loss of operation with the CYP27B1 variant presented considerable risk of MS. In 35 out of 35 instances, parents with one copy of the mutation transferred those genes to children with MS.
This research is demonstrating a correlation between the loss of function of CYP27B1 mutations with MS and low levels of vitamin D, further indicating the importance of studying vitamin D linkage to MS.
The MS Society of Canada will continue to follow advances in this area of research and will provide updates as they become available.