A large collaborating group of European researchers known as the “GAMES” (Genetic Analysis of MS in EuropeanS) Collaborative Group evaluated the clinical characteristics of 1,083 families with two or more close relatives with MS. Reporting in the January 30, 2007 issue of Neurology (2007;68:376-383), the investigators found that family members often shared some disease characteristics in common, such as similar ages at onset, but that the severity of disease experienced by one member could not reliably predict the severity of close family members.
Drs. Anke Hensiek, Allastair Compston (University of Cambridge, UK) and scores of collaborators in Europe, Turkey, Australia and the United States reported on clinical characteristics of their families collected for the GAMES study, originally established to search for genes that make people of European descent susceptible to developing MS. Of 1,083 families studied, 757 had two siblings with MS, 199 had one affected parent and one child, 72 had three or more affected siblings, and 55 had more complicated structures.
The researchers found that age of onset of MS was similar within a family, whether comparing siblings or parents. The clinical course of MS (patterns of disease such as relapsing-remitting, secondary progressive and primary progressive MS) was similar among siblings, but not between parents and their children. Severity of disease could not be predicted by the severity experienced by other family members.
In a press release, Professor Compston stated, “People should not draw personal conclusions for their own MS prognosis and expected disease severity from observing the condition of their relatives with MS.” The authors caution that because most of the families studied are of European descent, it is possible that their findings cannot be universally applied to MS families from other ethnic or racial groups.