RNase L is an enzyme found in all cells that is activated when a cell
is under attack by viruses, some bacteria and at least some toxins.
Upon activation it destroys both pathogenic and/or host mRNA thus putting
the cell into an 'antiviral state'.
Chronic fatigue syndrome in an individual is diagnosed by determining
the level of RNase L inhibitor mRNA or protein in peripheral blood mononuclear
cells. Significantly decreased levels of RLI mRNA or protein compared
to healthy control individuals indicates the presence of chronic fatigue
syndrome.