According to a recent article by theguardian, a Jordanian couple who had traveled to Mexico for fertility care by a US specialist, gave birth on April 6 to the world’s first baby born from a new procedure that combines the DNA of three people. The process is called a mitochondrial transfer and is still controversial and experimental. A team of doctors led by John Zhang, from the New Hope Fertility Center in New York, did the mitochondrial transfer hoping that the procedure would result in a healthy child.” While it does appear that the baby is healthy, there are many in the field of reproductive medicine who are decrying Dr. Zhang’s decision, raising concerns that “that the doctors had left the US to perform the procedure beyond the reach of any regulatory framework and without publishing details of the treatment” among other criticisms.
Dr. Zhang refutes those critiques, saying that he chose to do the procedure in Mexico simply because the lack of regulation would give him the best opportunity to help save a child’s life. The parents of the baby had suffered ten years of four miscarriages and two losses of their very young children. The mother carries in about one-quarter of her mitochondria the fatal gene for Leigh syndrome, which affects the developing nervous system of a fetus. Dr. Zhang removed the nucleus from one of the woman’s eggs and inserted it into a healthy donor egg from which the nucleus had already been removed. Then the egg was fertilized with the husband’s sperm. Five embryos were created but only one developed normally. That was implanted into the mother and the baby was born nine months later. Again, it does appear that the baby was born healthy.
This is not the first baby to be born of procedures that utilized the DNA of three people. In the 1990’s doctors attempted to boost the quality of a mother’s eggs by injecting cytoplasm (containing mitochondria) from donors and many of the resulting babies were born with genetic disorders. That procedure was consequently banned. Scientists both in favor of this new mitochondrial transfer and opposed to it raise many questions, including concerns about the methodology, the safety, and the reproducibility of the work that Dr. Zhang and his team did. Those concerns seem to be amplified by the work remains unpublished and thus unreviewed by the larger scientific community. However, details of the birth are slated to be presented in October at the American Society for Reproductive Medicine meeting in Salt Lake City.
Doug Turnbull, a neurology professor at Newcastle University who pioneered mitochondrial transfer in the UK, said the while this procedure offers hope to mothers who carry mitochondrial DNA mutations, but adds:
“There have been extensive discussions in the UK to ensure that families with mitochondrial disease get the best possible advice about their reproductive options and that any new IVF-based technique is appropriately regulated and funded. This abstract gives very little information about the technique used, the follow up of the child or the ethical approval process.”
Photo Credit: Ben Birchall/PA