Microarray technology and genes

In microarray testing, samples are arranged in a grid-like order, within a defined area, on glass microscope slides. This technology allows a huge number of genes to be surveyed at one time.

Samples appear as series of spots (that represent genes) which undergo a binding process and produce signals relating to the gene still present from the samples. It is the intensity of these spots (like an on/off type of mechanism) that provide the data—so for example, the intensity of one spot (CFS) can be compared to the intensity of the corresponding spot (control).

Agents are used to display the data in certain colors like red and green to help facilitate analysis. In one sample chart, Dr. Klimas pointed out how the red pattern was showing downregulated mitochondrial function, while the green one was showing upregulated cytokines.

In that particular study, gene expression helped to demonstrate a difference between sudden and gradual onset of illness. The importance of this technology is that it will help to identify specific gene markers associated with CFS and ultimately lead to better treatments.

Gene research has provided meaningful information about CFS (again, as taken from Dr. Klimas’ presentation chart):

A CDC study of 20,000 genes studied the activity of 26 genes—activity that could accurately predict which of 6 categories of chronic fatigue a patient had on the basis of symptoms and other clinical tests.

• Most of these genes are involved in immune system regulation, the adrenal gland, and the brain’s hypothalamus and pituitary glands.
• Studies of hormones and immune factors confirm these findings.
• Kerr’s study revealed differential expression of 35 genes in 25 patients as compared with 25 controls. The differential expression in patients suggested T-cell activation and disturbances of neuronal and mitochrondrial function.

Other studies have pinpointed 5 specific genes that correlate with an apparent susceptibility to chronic fatigue—more specifically with levels of serotonin and glutamate affected.

Speaking of the recent CDC study, Dr. Klimas felt newspapers had misreported the study findings and the role of stress. She stated there is a “huge difference” between stress as implied in these articles (assuming she meant how one might psychologically cope under pressure) and one’s stress response.

In the latter, there are biological defense mechanisms called into action, which involve everything from the autonomic nervous system, the cardiovascular system, the neuroendocrine axis, and the immune system. These systems react automatically to stressors.

Such stressors would include environmental triggers, infections, or disruptions caused by illness. Klimas also announced that on or around June 1st, the CDC is supposed to release another press release. She is optimistic this may have something to do with upcoming treatments.