Are there any tests that can indicate if a person will develop MS even if they have no symptoms, but has multiple family members with MS?

Here is My Question:
Are there any tests that can indicate if a person will develop MS even if they have no symptoms, but has multiple family members with MS?

Answer:
The question is, How can you determine if you are at high risk of MS before you develop symptoms or exam findings?

For many years, we have known that people with MS often exhibit potentially prodromal symptoms, sometimes more than a decade before a definite diagnosis can be made even using the newer diagnostic criteria for MS.  To my knowledge the first prospective study to report potential prodromal symptoms was the optic neuritis treatment trial (ONTT) designed and led by Roy Beck and first reported in early 1990's. A major secondary goal of the ONTT was to determine risk factors for a person to develop MS after an isolated episode of optic neuritis (ON). As you may know, optic neuritis is a common first symptom of MS but only 50 % ( a flip of the coin) of people experiencing optic neuritis develop MS; the investigators want to find out how to better predict the risk of MS after ON.

​There have been many reports from this study over the years of the predictive role of brain MRI findings in determining a group with a higher risk of developing MS. What people often forget is that the investigators also asked patients presenting with acute optic neuritis  (an no knowledge of the MS) if they had ever experienced prior neurological symptoms before this episode of optic neuritis. It turned out that many people did experience prior symptoms such as paresthesia (i.e., unusual sensations), vague cognitive complains, unusual episodes of fatigue, and subtle urination problems to name a few, that were either not investigated or attributed to another cause. When the investigators lumped these symptoms together-calling them "vague neurologic symptoms"- and continued to follow patients over the years, they discovered that these "vague neurologic symptoms" were statistically associated with the future development of MS. 

Fast forward to the present and investigators have developed a more urgent interest in learning how to identify people with MS prior to the onset of symptoms by using a combination of prodromal symptoms, family history and genetic risk factors, and various biomarkers. The main motivation for learning to identify people with presymptomatic MS is the increasing number of studies suggesting that earlier initiation of disease modifying treatments leads to improved long-term outcomes. Many of these studies are in early stages of development and will want to recruit people with a family history of MS, since a positive family history already increases the risk of MS by a percentage based on the relationship of the relative(s).  Stay tuned for more information.

Great question by the way
Revere P (Rip) Kinkel, MDProfessor Emeritus
Neuroscience Department
University of California San Diego