The W.H.O. committee described an invented scenario where researchers from a rich country want to do a clinical trial of sickle-cell gene editing in sub-Saharan Africa, where the disease is prevalent. If the trial succeeds, the gene-editing treatment would be too expensive for all but very few citizens of the country where it is to be tested.
Another hypothetical situation involves a gene-editing trial to correct a gene mutation that causes Huntington’s disease, a progressive brain disorder. People who inherit the mutated gene will develop Huntington’s disease with absolute certainty. If the gene-editing experiment succeeds, it may spare them that horrific disease. And because the editing does not involve sperm and eggs, the changes will not be heritable.
But it would take years, perhaps even decades, to know if study participants whose genes were edited were protected from Huntington’s disease. Participants would not be freed of the terrible fear that, despite the gene editing, they might still develop the fatal brain disease.
In such a scenario, the W.H.O. group asked if there were more rapid ways of assessing the treatment’s effectiveness. It also proposed that researchers consider the psychological burden on participants who are left hoping they are cured but not knowing for sure.
Yet gene editing is here and holds enormous promise, the committee said. The W.H.O. has started a registry of studies underway and says it already includes 156 experiments involving genes that are not in sperm or eggs.
The W.H.O. committee stressed that each country must have guidelines to be sure the research is conducted ethically and with appropriate oversight, and with conditions in place to ensure access and social justice. With the costs of treatment expected to be very high, at least at first, the group said the goal must be to ensure that the benefits of gene editing accrue equitably to people around the world.
“That is not an easy challenge,” said Françoise Baylis, a committee member who is a medical ethics researcher at Dalhousie University in Halifax, Nova Scotia.