Studies in animals, including one described recently in Wired, show that the gene manipulation technique CRISPR has a habit of inserting bacterial DNA along with the desired sequences into various sites in chromosomes, with unknown consequences. Even more alarming was a news article last month in the scientific journal Nature that bore the title “CRISPR gene editing in human embryos wreaks chromosomal mayhem.”
Thus, even if the modification method were perfect, the variability of human biology means that we won’t know what the outcome will be. The new results, however, cast strong doubt on the CRISPR technique itself. In the words of the Nature news story, “the process can make large, unwanted changes to the genome at or near the target site.”
Scientists who overstep cultural norms or federal restrictions rarely suffer consequences beyond the loss of their federal funding. In the U.S., private corporations or even states will define their own acceptable practices regarding embryo engineering. How these entities define too far, too fast, is completely subjective — a recipe for human disaster.
The techniques of embryo engineering have now been shown to be flawed. Embryos are just too complex to engineer. We must ban, not simply pause, gene editing of human embryos before biomedical entrepreneurs start offering clients the opportunity to modify their offspring, threatening their health and hijacking their identities before they are even born.