“The scientists begin by inserting “ne…

“The scientists begin by inserting “neuroprotectant” genes, such as estrogen, into a modified version of herpes simplex virus. Why herpes? For starters, the virus is able to quietly enter nerve cells. Ordinarily, this viral invasion would lead to an acute infection and cell death. But Sapolsky and his team have engineered the virus so that it can’t multiply and commandeer the cell. Instead, it just lurks in the nucleus, waiting to be turned on and express these protective snippets of DNA.”