Now that we can alter our genetic code, should we?

Columbia physician Siddhartha Mukherjee is illuminating the brave new world of genomic medicine, paying equal attention to the science and the ethical quandaries raised by gene sequencing and editing technologies.

In his book The Gene: An Intimate History, Mukherjee traces the evolution of our understanding of genetics, from Mendel’s peas through Crick, Watson, and Franklin’s discovery of the double helix structure of DNA to the present. Along the way, he considers the ethical issues that attend each breakthrough, from the eugenics movement of the early twentieth century to today’s debate over intentionally changing human genomes.

A woman carrying a BRCA-1 mutation has nearly a 60 to 70 percent lifetime risk of developing cancer in her breasts or ovaries during her lifetime. Mukherjee points out, however, that we cannot predict when the cancer will occur or how severe it will be. Now that we have the capacity to screen for the BRCA-1 mutation, a woman will have to live with the knowledge that she may develop cancer without knowing when. She is a previvor—anticipating cancer and imagining survivorship—a completely new type of patient facing new kinds of choices.

The BRCA-1 mutation may eventually be edited out of the human genome, depending on the choices made by scientists and politicians today. Mukherjee examines the consequences of such editing—for one, the effects of heritable genome edits will be multigenerational, stretching far into the future. He points out that we do not fully understand the interaction among genes and the complex ways that gene and environment intersect, so editing in one place will manifest in other places in ways that we cannot anticipate.

As we celebrate the new medical interventions made possible through precision medicine, Mukherjee reminds us that we need new biological, cultural, and social precepts, keeping in mind our responsibility to all human beings—our ancestors, our descendants, and ourselves. Learn more.