Another Glimpse: “Biological Basis” implicated in small CDC genetic profiling study.
The CDC has released a small study using powerful genetic profiling techniques. Genetic profiling is a cutting edge technology that allows researchers to view a “snapshot” of thousands of physiological processes in the body. The study, published on Dec 1, 2003, in the debut issue of the obscure Journal of Translational Medicine, compared 23 CFIDS samples to healthy controls. As in previous studies using genetic profiling, researchers were able to easily distinguish between CFIDS samples and healthy controls.
This study was different than previous CFIDS genetic profiling studies in that it showed the CFS case definition could be corralling very different groups of patients. Researchers theorize that illness onset being the key-differentiating factor. “Different gene expression profiles among those who describe a difference in illness onset imply distinct etiological or triggering events, and shows that these differences are maintained well into the disease process”. Those patients whose illness began suddenly over the course of a week were clearly delineated from those whose illness slowly developed over the course of several months. Previous studies have shown that the currently broad, integrative CFS case definition may not be accurately catching a homogeneous group of patients.
Genes related to purine and pyramidine metabolism, glycolysis, oxidative phosphorylation, and glucose metabolism were singled out as the most differentially expressed. Researchers state that the results “imply fundamental metabolic perturbations that will be further investigated and illustrates the power of microarray technology for furthering our knowledge of CFS.” They theorize that, given their results, RNA processing proteins, and “alterations in effective antimicrobial response” may yield more answers to unlocking the mysteries of CFIDS.
The authors of the study caution that the study's samples were limited in size, and the number of possible genes to be studied are far beyond the 3800 that were examined in their research. They also caution that the 23 women selected for the study are far from a comprehensive set of samples. However, they do believe the results are compelling evidence that CFS has both a microbiological foundation, and the current CFS case definition is not corralling a homogeneous group of patients. More genetic profiling studies are in the pipeline.