Research: Certain EBV types are not associated with MS

Epub ahead of printLay et al. Epstein-Barr Virus Genotypes and Strains in Central Nervous System Demyelinating Disease and Epstein-Barr Virus-Related Illnesses in Australia.Intervirology. 2012 Jan 24.

Objectives: To identify Epstein-Barr virus (EBV) genotypes and strains in samples from individuals with and without a first diagnosis of central nervous system (CNS) demyelinating disease (a possible precursor to multiple sclerosis) or CIS and patients with EBV-associated diseases in Australia.

Methods: Samples from 55 EBV DNA and serology positive subjects including individuals with (n = 17) and without (n = 21) a first clinical diagnosis of CNS demyelination and patients with EBV-related diseases (n = 17) were examined. EBV genotype and strain were identified by sequence mutations within the Epstein-Barr nuclear antigen-2 region (EBNA-2) using DNA sequence analysis.

Results: Both EBV genotypes, A and B, were detected (genotype A, 54/55, 98.2%; genotype B, 1/55, 1.8%). Within genotype A, GD1 was the most commonly detected strain (42/54, 77.7%), followed by B95-8 (9/54, 16.7%) and M-ABA (3/54, 5.6%). Genotype B, strain AG876, was found in one individual with CNS demyelinating disease.
Conclusions: EBV genotype A and the GD1 strain were the common EBV genotypes isolated from individuals with and without CNS demyelinating disease, and in subjects with various EBV-related diseases. Although disease-specific genotypes or strains were not identified, this study provides useful insights into the molecular epidemiology of EBV infection in Australia.

"Please note that EBV is a family of viruses; i.e. EBV has evolved into two main genotypes (sub-species) and many strains. The question remains is there a specific strain of EBV that is associated with MS? This study tries to address that question. Unfortunately, the strains circulating in Australia seem to be relatively homogeneous. This data does not support the presence of a MS-specific strain. This would mean that of if EBV caused MS it would be the host response to the virus that is important rather specific viral factors that causes MS."