A few examples of what’s coming might be instructive. Research is presently underway into the prospect of the genetic enhancement of physical strength (we’ve already mentioned muscle enhancement through the use of drugs). Science has identified the genes that regulate the proteins that mediate muscle growth. If we insert these genes, synthetically produced, directly into muscles we could stimulate the production of these muscle growth proteins. Or, we could introduce the genes directly into human embryos, created in the lab, with the hope that they (the genes) would be incorporated into the functional genome of the growing person. Both types of insertion experiments have proved successful in studies with rats: muscle growth was increased in healthy adult rats and muscle decline was deferred in rats of advanced age.
Since we already treat elderly patients with drugs for increasing muscle mass and strength (a seemly legitimate therapeutic practice), why not enhance muscle strength through genetic engineering? Why not open these treatments to younger persons before they grow old in order to prevent or defer the effects of aging, called in the literature “age retardation”?
This raises the question of the morality of life extension research…