BBC: Vitamin D helps control MS gene

"Exactly how the gene-environment interaction alters MS risk is yet to be determined; one explanation could be an effect on the thymus - a part of the immune system which produces T cells to attack invaders such as bacteria and viruses.  It is thought that in people who carry the gene variant, a lack of vitamin D during early life might impair the ability of the thymus to delete rogue T cells, which then go on to attack the body, leading to a loss of myelin on the nerve fibres."

This is an interesting read!

http:  //news.bbc.co.uk  /1/hi/health/7871598.stm

)take out spaces)

[jensequitur]

whups, sorry!  Didn't see that engineer had already posted this.