- Last Updated: 25 November 2015 25 November 2015
Genetic component to CFS
Dr. Komaroff asked if there is a genetic component to CFS, and then stated that the answer is almost surely yes. There are certain molecules that are genetically-linked, called histocompatibility antigens which are found with increasing frequency and are more prevalent in this illness.
(Significantly increased are DR-4, DR-3, DQ-3, and DQ-1.)
Twin studies show about 51% hereditability in CFS—identical twins are much more likely to have the illness than fraternal twins.
Neuroendocrine gene variants: Are there genes that are simply built differently from birth that people with CFS inherit, that are different from most peoples’ version of that gene? There do appear to be a few such genes, as shown in studies done by the CDC.
Gene expression studies in CFS
Perhaps a more useful mode of investigation comes from studies that consider gene expression—i.e., the genes which are actually turned-on during specific cell activity. What a cell does in a particular physical process depends upon which genes are turned-on and which genes are not.
During the past ten years with new technology to measure gene expression, it is now possible to look at the white blood cells of CFS patients and determine which genes are turned on or off in contrast to those same genes in healthy individuals, individuals with depression, and individuals with other illnesses.
In fact, patients with CFS do have different patterns of gene expression, such as in genes that are involved in immune system activation, in energy metabolism, in producing neuro-hormones that are involved in the stress response.
“Many studies from different laboratories show that the genes are activated more often in patients with CFS. Here is another objective abnormality in this illness that distinguishes CFS patients from healthy people,” said Dr. Komaroff.