The possibility that social factors might regulate gene expression first emerged in the context of bio-behavioral health research. Social stress and isolation have long been known to affect the onset and progression of disease (Seeman, 1996). That effect is particularly strong for viral infections, where social factors have been linked to increased replication of cold-causing rhinoviruses (Cohen, Doyle, Skoner, Rabin, & Gwaltney, 1997), the AIDS virus, HIV-1 (Cole, 2008), and several cancer-related viruses (Antoni et al., 2006). Viruses are little more than small packages of 10-100 genes that hijack the protein production machinery of their host cells (us) to make more copies of themselves. As obligate parasites of our living cells, viruses have evolved within a micro-environment structured by our own genome. If social factors can regulate the expression of viral genes, that suggests that our own complement of ~22,000 genes is likely to be regulated in biologically significant ways as well.
