J Neurol 2003 May;250(5):607-11
Schmidt S, Papassotiropoulos A, Sotgiu S, Kolsch H, Arru G, Fois ML, Haase CG, Schmitz S, Konig N, Harzheim M, Heun R, Klockgether T.
Dept. of Neurology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
Interleukin-6 (IL-6) plays an important role in the regulation of the inflammatory response in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE).
Previous reports indicated that the C allele of a variable number tandem repeat (vntr) polymorphism located in the 3'flanking region of the IL-6 gene (IL-6) is associated with reduced activity of IL-6 in vivo.
Since disease-modifying genes are likely to contribute to phenotypic differences in MS patients, we tested the hypothesis that the IL-6 C allele is associated with the clinical course of MS.
The IL-6 C allele was equally distributed between 217 MS patients of German Caucasian origin and 111 age-mached healthy controls.
Stratification of patients according to the course of disease revealed no significant difference of IL-6 C allele distribution between patients with primary progressive and those with either relapsing-remitting or secondary progressive MS although IL-6 C allele was more frequent in patients with RR-MS.
Since IL-6 C allele has been associated with a benign course in Sardinian MS patients, we further analysed an independent sample of 125 Sardinian MS patients revealing that IL-6 C allele was much more frequent than in German MS patients.
Taken together, a disease-modifying effect of IL-6 C allele could not be demonstrated in MS patients of German Caucasian descent.