The first known human trial of three-person in vitro fertilization (IVF), a procedure currently banned in the United States, is about to be underway in Greece. The goal of the trial is to evaluate the procedure’s safety and efficacy. It may also eventually give us a better understanding regarding the procedure’s long term side effects.
Three-person IVF involves using donor eggs, stripping them of their nuclei, and then inserting the intended mother’s DNA in its place. Those eggs are then fertilized with sperm. The resulting embryos, therefore, contain genetic material from three people. The amount of donor DNA makes up only about 0.2 percent of the embryo’s total DNA. The procedure is banned in the United States because the long term effects having three people’s DNA in an embryo is not well understood.
The idea behind three-person IVF is that it may help older women with poor egg quality conceive a genetic child of their own. Currently, many older women are using donated eggs from younger women to conceive, but the genetic material in those eggs remains that of egg donors. Three-person IVF may provide another option for these women to conceive and use their own DNA.
Three-person IVF may also be used to prevent the inheritance of mitochondrial diseases. Mitochondria is found in an egg cell’s cytoplasm and carries its own DNA. This DNA is separate from chromosomal DNA. Babies inherit all of their mitochondrial DNA from the female egg, so if a woman carries a mitochondrial mutation, her baby will likely inherit it. Mutations in mitochondrial DNA can lead to severely debilitating and/or fatal conditions. By using the mitochondrial DNA from an egg donor and the chromosomal DNA from the intended mother, physicians and scientists may be able to help women with mitochondrial mutations conceive healthy children. Three-person IVF for mitochondrial diseases is currently legal in the United Kingdom.
The plan of the pilot trial in Greece is to enroll 25 women under the age of 40 who failed to conceive with traditional methods of IVF. This would be the largest trial of three-person IVF to date. The researchers plan to monitor the health of all of the babies born from the study until they are 18 years old. The goal of the study is to provide some data regarding the safety and efficacy of the procedure and the long term side effects.
To date, more than 35 live births from three-person IVF have been reported world-wide. Since the procedures were performed in different countries and different facilities with differing techniques, it is difficult to obtain meaningful data on the procedure’s safety and efficacy. The trial in Greece may help us better understand the implications of this controversial fertility treatment.