Environmental factors may play a role during childhood, with several studies finding that people who move to a different region of the world before the age of 15 acquire the new region's risk of MS. If migration takes place after age 15, the persons retain the risk of their home country. Some evidence indicates that the effect of moving may still apply to people older than 15.
Environmental factors may play a role during childhood with several studies finding that people who move to a different region of the world before the age of 15 acquire the new region's risk of MS If migration takes place after age 15 the persons retain the risk of their home country Some evidence indicates that the effect of moving may still apply to people older than 15