The halt Jennifer Doudna called for when she invented CRISPR-Cas9 in 2012 is set to continue as an international commission concluded there is still insufficient evidence that precise genomic changes can be rapidly made to the germline without undesired changes.
At the time, and still currently, it was illegal in much of the world to use a genetically engineered embryo to establish a pregnancy. In China, it is prohibited under a 2003 ministerial guidance to IVF clinics. He has since been sentenced to prison.
While the report maintains the need for continued research and extensive conversation before any country permits germline editing of human embryos, it does provide a tentative framework for how this could look in the beginning.
However, the report says this should only be done for persons whom have no option for having a genetically related child that does not have the serious monogenic disease. If there is a chance some biological children will not inherit the disease, the commission cautions against CRISPR-Cas9 for many reasons, chief among them being a healthy embryo could become affected.
Serious monogenic diseases above situation is the only for which the report provides a “responsible translational pathway” from preclinical research to application in humans. The commission does account for a second category where genome editing may be appropriate, but certain parameter must be met. In this case, a person(s) wishing to have a child must have a 25% or less change of unaffected embryos, and have attempted at least one cycle of preimplantation genetic testing without success.
If HHGE moves forward, pre-clinical and clinical data will be critical to its success. Preclinical data must prove safety and efficacy, including that the intended edit was successful and no other modifications occurred. A proposal for clinical use should include plans to evaluate human embryos prior to implantation, including through a biopsy performed within 5-9 after fertilization at the blastocyst stage. Monitoring during pregnancy and long-term follow up of resulting children and adults will also be vital to the success of HHGE.
Lastly, the report recommends the establishment of multiple regulatory bodies to oversee HHGE progress, including at least one per nation, an independent, multidisciplinary International Scientific Advisory Panel, as well as a second international body to focus specifically on the societal implications of HHGE.
