It's just over a year since Dr He Jiankui's controversial announcement that he had created the world's first genome-edited babies (see BioNews 977). This has sparked international debate over the use of the approach in humans – but what may be missing in the discussion are moral questions concerning the research that would precede clinical applications.
Genome editing is a method that allows scientists to alter the DNA of organisms. Researchers are using various technologies in their studies, including the use of CRISPR/Cas9, removing mutated genes that cause heritable diseases and conditions, eg Parkinson's or muscular dystrophy.
However, there are risks associated with CRISPR. To advance genetic methods that are safe and effective for humans, much research is needed. It is possible to cut DNA at the wrong spot: off-target effects where edits are performed in the wrong place and scientists are uncertain as to how this might potentially affect patients. The other challenge is mosaicism where only some cells carry the edit but not others.
Accordingly, fundamental research is required to check the safety and accuracy of genome editing. And clinical applications can be considered only after thorough studies have been conducted.
However, there are important ethical issues to be discussed concerning the studies that would precede this stage. For instance, scientists may need to do testing on human embryos. For such experiments, many eggs are required for fertilisation in the lab to produce these embryos.
Recently, Dr Emilia Niemiec and Dr Heidi Carmen Howard at Uppsala University in Sweden, raised these ethical matters in their Correspondence to Nature. The authors stressed that women who decide on egg donation should comprehend the ethical issues to enable them to make an informed decision on whether or not to donate their eggs.
Egg donation involves health risks for these women and the financial compensation they may receive could amount to an inducement for economically disadvantaged donors. Thus, the studies, which are likely to precede clinical applications of genome editing in humans, pose their own set of ethical issues.
An essential factor to consider is whether, before egg donation, adequate counselling was presented to the donors to ensure they were fully informed about the health risks involved. These risks are due to ovarian stimulation to obtain the eggs.
The process of egg retrieval is invasive and painful. Elevated doses of ovary stimulating drugs are needed to induce the ovaries to create numerous eggs. Some egg donors may experience ovarian hyperstimulation syndrome (OHSS), a condition that could cause nausea, bloating, kidney failure and even death (see BioNews 973 and 975).
There have been reported deaths of patients after undergoing IVF treatment. A possible long-term risk of ovary stimulating drugs is the development of cancer. Some studies have suggested a link between fertility drugs and certain types of cancers, though researchers speculate that these may not develop until donors are in their 50s or 60s.
Egg collection and ovarian stimulation are associated with more health risks than the removal of other human tissues for research. Egg donors are exposed to an increased risk of morbidity or mortality associated with the stimulating hormone treatment needed for egg retrieval. If they were not sufficiently told of the various health risks, it is questionable whether informed consent is actually provided by the women.
Despite the frequent use of ovarian stimulation and egg retrieval in IVF cycle, there has been a shortage of studies done on the short- and long-term adverse consequences of ovarian stimulation and egg donation. So there are uncertainties surrounding the effects of the drugs and procedures.
The issue of pecuniary gain for egg donors in research raises the concerns of commodification of human tissues and commercialisation of research. Donations of body parts and tissues to research are expected to be altruistic. Commodification refers to an attachment of economic value to a thing which locates outside the economic sphere.
The value of some matters, such as the human body, cannot and should not be expressed in terms of money. Human eggs should not be sold by donors. Some women may be primarily enticed by money to donate their eggs without receiving adequate information ie, the health risks associated with egg extraction. This is especially true for poorer women who may ultimately sell their eggs out of desperation.
At the very least, egg donors should be reimbursed for their services. Egg donors receive no direct therapeutic benefit from the study. But in contrast to sperm or blood donation, the process of egg donation is far more complex and risky. It is essential to differentiate between payment for the commodity of the gamete and payment for the service provided, that is, reimbursement. Egg donors should not be out-of-pocket after donation, so their participation is expense neutral. However, payment beyond reasonable costs should not be permitted to prevent the risk of exploitation of women and the commodification of human eggs.
Eggs donated from younger donors are preferred as they are considered as being of better quality compared with eggs from older women. With these ethical issues surrounding egg donation in genome editing research, it is critical there is sufficient regulatory framework in place to safeguard the rights of egg donors.