Imagine being diagnosed with a debilitating or deadly disease, only to be cured by doctors able to alter your very DNA. It sounds like science fiction, but it is the promise of gene therapy. And that promise seems closer than ever to being fulfilled.
Over the past few years, one particular gene editing technology has leapt to the forefront. It’s called CRISPR, and researchers say it has the potential to cure a wide range of diseases – HIV, sickle cell anemia, muscular dystrophy, cystic fybrosis, and some cancers. It could also be used in agriculture, to enhance food crops or animals.
But serious ethical questions are cropping up. CRISPR can be used to alter human embryos, or eggs and sperm. Any such changes would be heritable, and some worry it could be used to not only prevent devastating diseases, but to change features like eye color or intelligence.
Researchers and ethicists are divided on whether or how to proceed with the use of CRISPR gene editing. Some scientists have called for a moratorium on the use of the technology until safety issues have been resolved, and there are policies in place to address ethical questions. In a recent public opinion poll, 65% of respondents said altering embryonic genes to reduce disease risks should be illegal; 83% opposed allowing gene editing to enhance intelligence or change physical appearance.
But others liken the debate to previous ones over technologies like in vitro fertilization and cloning, which sparked intense but, ultimately, short-lived controversies. In the former case, that's because most people found IVF babies to be indistinguishable. In the latter case, the infeasibility of human cloning rendered the debate moot.
CRISPR lies somewhere in between, with the potential for eugenics-style genetic enhancement limited less by the technology, itself, than by the inherent complexity - and our incomplete understanding - of traits, like strength or intelligence. In other words, even the best gene editing technology is of littke use if we don't know where to aim it, or if environmental and lifestyle factors outweigh genetics in producing the desired end result.
In some regards, trying to limit the use of CRISPR is trying to put the genie back in the bottle. Researchers in the U.K. and China say they've already altered human embryos. Both agricultural and medical applications are under development. The real question at this point seems not to be whether CRISPR will be used, but how it will be used, and how use will be overseen.