APOE epsilon status in Hungarian patients with primary progressive multiple sclerosis

Apolipoprotein E (ApoE), an important glycoprotein in the transport, uptake and redistribution of cholesterol, is necessary in nerve tissue repair. The APOE gene (APOE) is involved in neurodegenerative diseases, the best-known association being that between the APOE ε4 allele and Alzheimer's disease. Multiple sclerosis (MS) is a chronic inflammatory neurological disease. The aim of this study was to assess (multicentre assessment) the possible influence of the APOE gene on the susceptibility of primary progressive MS (PPMS) in Hungary. Polymerase chain reaction and restriction fragment length polymorphism were carried out on DNA isolated from 135 volunteers. The number of PPMS patients without the ε2 allele was found to be remarkably high, whilst the ε2 allele was overrepresented in the RRMS group. A markedly high frequency of the ε4 allele was found in the PPMS group and a very low frequency in the HC group. With regards to the clinical parameters, significant differences were observed between the RRMS and PPMS groups. Differences were also detected regarding the EDSS and MSSS scores when the patients were grouped by the presence or absence of the ε2 allele. All of the observed differences in the clinical parameters disappeared when the patients were further stratified by the type of MS. Our findings suggest that the presence of the ε2 and ε4 alleles may play a role in the development of the disease. However, if any type of the disease has already developed the alleles show no association with the clinical parameters.