Reduced levels of oestrogen receptor {beta} mRNA in Swedish patients with 
chronic fatigue syndrome.

J Clin Pathol. 2006 May 26; [Epub ahead of print]

Gräns H, Nilsson M, Dahlman-Wright K, Evengård B.

Karolinska Institutet, Sweden.

NLM Citation: PMID: 16731592


BACKGROUND: Chronic fatigue syndrome (CFS) is an illness with unknown 
aetiology and pathophysiology. The sex difference observed for CFS 
indicates a role for oestrogen and oestrogen receptors (ERs) for disease 
development. Furthermore, an immuno-mediated pathogenesis has been 
suggested for CFS which provides an additional connection to oestrogen, 
which display immunomodular functions.

AIMS: The aim of this study was to investigate a possible association of ER 
mRNAs and two ERbeta single nucleotide polymorphisms (SNPs) with CFS.

METHODS: Messenger RNA levels of ERalpha, ERbetawt and ERbetacx were 
investigated in peripheral blood mononuclear cells (PBMCs) from 30 CFS 
patients and 36 healthy controls by quantitative real-time PCR. Two ERbeta 
SNPs were scored in the same material.

RESULTS: The CFS patient group showed significantly lower mRNA expression 
levels of ERbetawt compared with the healthy control group. No differences 
were observed for ERalpha or ERbetacx between patients and controls. There 
were no significant differences in frequency for the investigated ERbeta 
SNPs between cases and controls.

CONCLUSIONS: The reduced ERbetawt expression levels observed in this study 
is consistent with an immune-mediated pathogenesis of CFS. Additionally, 
the observation that ERbetawt expression is decreased in CFS could provide 
an entry point to identify interesting, potentially disease causing, 
candidate molecules for further study. A possible connection between 
oestrogen, ERs and CFS should be further evaluated.