The proinflammatory cytokine interferon (IFN)-gamma has been shown to influence the course of multiple sclerosis (MS). The IFN-gamma (IFNG) contains a multiallelic dinucleotide repeat in intron 1. To investigate whether alleles at this locus influence susceptibility to MS, we performed linkage and familial association analyses on 100 sibling pairs from four Nordic countries, and case-control association analysis on 220 intermediately disabled sporadic MS patients and 266 controls. To determine the effect of the polymorphism on disease outcome, we compared genotype frequencies in the most and least disabled octiles of a total cohort of 913 cases. We also measured IFN-gamma mRNA levels in unstimulated peripheral blood mononuclear cells from 46 MS patients and 27 controls grouped according to IFNG intron 1 genotype. Both nonparametric linkage analysis and transmission disequilibrium testing of the 100 sibling pairs produced negative results. Genotype frequencies for intermediate-MS patients did not differ significantly from those for controls; nor did genotype frequencies in the benign-MS octile differ significantly from those in the severe-MS octle. Comparison of IFN-gamma mRNA levels in genotype-conditioned subgroups revealed no significant differences. Thus, alleles at the IFNG intron 1 dinucleotide repeat appear to affect neither MS susceptibility and severity nor IFN-gamma mRNA expression in vivo.
Neutralizing antibodies (NABs) occur frequently in patients receiving interferon (IFN)-beta for multiple sclerosis (MS), but it is unclear whether occurrence of NABs is predictive for the persistence of NABs during continued IFN-beta therapy.
The authors used an antiviral neutralization bioassay to measure NABs blindly from 6 months up to 78 months in patients with MS who were followed for at least 24 months during treatment with IFN-beta. Patients were classified into three groups: 1) persistently NAB-negative patients, defined as patients without any positive samples at any time; 2) definitely NAB-positive patients, defined as patients who had at least two consecutive positive samples; and 3) patients with fluctuating NAB-positive and NAB-negative samples.
A total of 455 patients were included in the study. Overall, 52.3% of the patients were persistently NAB-negative, 40.9% became definitely NAB-positive, and the remaining 6.8% were fluctuating. More patients treated with IFN-beta-1a (Avonex) remained NAB-negative (p
Little is known about the impact of parental multiple sclerosis (MS) on offspring's educational attainment. The objective of the study was to examine educational achievements in offspring of parents with MS compared with matched children of parents without MS in a nationwide register-based cohort study. Children of all Danish-born residents with onset between 1950 and 1986 were identified by linking the Danish Multiple Sclerosis Registry with the Civil Registration System. Twins, children with MS, and emigrated persons were excluded. The reference cohort consisted of randomly drawn individuals from the Civil Registration System without parental MS matched 8:1 to the MS offspring by sex and year of birth. Information about education was linked to the cohorts from nationwide educational registries. We included 4177 children of MS parents and 33,416 reference persons. Children of MS parents achieved statistically significant higher average grades than the reference cohort in their final exam of basic school with a mean grade difference of 0.46 (95 % CI 0.22-0.69; p = 0.0002). We found no difference in achievement of educational level above basic school (OR 1.04; 95 % CI 0.98-1.10; p = 0.20). There was a trend toward more MS offspring attaining health-related educations (OR 1.10; 95 % CI 1.00-1.21; p = 0.06). In conclusion, children of MS parents showed a small advantage in grade point average in final examinations in basic school, and they more often tended toward health-related educations. This study revealed no negative consequences of parental MS on grades and highest educational level achieved.