Background: Fibromyalgia (FM) and chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME) are believed to be two separate illnesses that are diagnosed using separate but overlapping clinical criteria; to date there are no biological markers for either condition. The symptoms of both disorders can differ markedly in presentation, frequency and intensity and therefore it is necessary to distinguish between the subtypes. Since recent studies have begun to determine the genetic background of these diseases, the authors suggest the use of single nucleotide polymorphism (SNP) analysis to investigate their different genetic profiles. Methods: A group of 403 women (186 FM and 217 CFS/ME) were recruited for the study using the American College of Rheumatology 1990 and the US Centers for Disease Control and Prevention (CDC) research definition for FM and CFS diagnosis criteria, respectively. The Fibromyalgia Impact Questionnaire and the CDC Symptom Inventory questionnaires were used to define severity subgroups. For each sample, 107 SNPs were genotyped by SNPlex™. An independent second association study with 282 women (126 FM and 156 CFS/ME) was used to validate the results. Results: Fifteen SNPs were identified that were able to discriminate between FM and CFS patients with a likelihood ratio (LR+) of 11.5 (95% specificity). Analysis of further SNPs allowed differential genetic profiling between the most aggressive FM phenotype and the mild forms (LR+ 12.4) and between a severe CFS/ME phenotype and a milder one (LR+ 12.4). Conclusions: In this study, the authors claim that FM and CFS/ME are, at least in a subgroup of patients, two separate diseases with an important genetic component and suggest that CFS/ME diagnosis should be an exclusion criterion for FM diagnosis. In addition, severe cases might be different disease subtypes with distinctive genetic profiles.
|Number of pages||24|
|Journal||Journal of Clinical Research|
|Publication status||Published - 2008|
- Chronic fatigue syndrome
- Myalgic encephalomyelitis
- Single nucleotide polymorphism