What is MS and why women are at greater risk l GMA

Following Christina Applegates announcement that shes been diagnosed with multiple sclerosis, ABC News chief medical correspondent Dr. Jen Ashton weighs in on MS and what to look for. LEARN MORE: Christina Applegate reveals she s been diagnosed with MS: SUBSCRIBE to GMA s YouTube page: VISIT GMA s homepage: SIGN UP to get the daily GMA WakeUp Newsletter: , ChristinaApplegate, MultipleSclerosis, GMA