In a bid to determine factors linked to the most debilitating forms of multiple sclerosis (MS), Johns Hopkins Medicine researchers say they have identified three so-called “complement system” genes that appear to play a role MS vision loss. The researchers were able to single out these genes—known to be integral in the development of the brain and immune systems—by using DNA from MS patients along with high tech retinal scanning. The investigators say these genes could serve as markers for monitoring and predicting progression and severity of MS, an unpredictable disorder in which the immune system eats away at protective insulation around nerve cells. Peter Calabresi, M.D., explains the findings here.