In a world first, a controversial in vitro fertilization method has delivered a baby girl to a previously infertile couple in Kiev, Ukraine.
The pronuclear transfer technique, also called three-person IVF, is a world first but the second to produce a baby born with DNA from three parents, next to a slightly different method conducted in Mexico last year.
Here’s what happened: the team of doctors at the Nadiya Clinic for Reproductive Medicine in Kiev fertilized the mother’s egg with her partner’s sperm and afterward transferred the combined DNA into an egg from a donor. The baby, born last Jan. 5, maintains the genetic makeup of her parents and a tiny bit of genes from the female donor.
The IVF Process
Doctors came up with the three-person IVF to assist women at risk of passing on mitochondrial disease, or serious genetic disorders, to have a healthy offspring. Eggs from patients with faulty mitochondria are collected alongside those from donors with healthy ones.
The team, however, used the method on an infertile couple instead of one carrying a mitochondrial condition. The 34-year-old mother suffers from “unexplained infertility,” according to the clinic’s director Dr. Valery Zukin.
Leading the “highly experimental” work, Zukin said they had a hunch it would work well for the couple. He cited a second patient in a similar predicament, expected to give birth early this March.
Scientific, Ethical Concerns
Pronuclear transfer was approved in the United Kingdom last 2015, although only for women with mitochondrial disease and with no baby born from the technique in the country yet.
Some experts raise the concern that the genetic tweaks produced in a baby girl could be passed onto her kids.
"I do think it's highly significant that this is a girl because we know for sure that she will be passing on her mitochondrial DNA through her maternal line," said Lori P. Knowles, from University of Alberta School of Public Health, in a CNN report.
Male babies that carry donor mitochondria cannot transfer their modified genetics onto their future children, as once a sperm merges with an egg to form an embryo, the male mitochondrion dies and leaves the embryo with only mitochondrion from the mom’s egg.
Once the baby girl’s children inherit these genetic tweaks, there will be “a really bright line” that should not be crossed until strict scientific testing proves safety, Knowles explained.
Zukin said that in the case of the Kiev couple, the method did not lead to a “suitable male embryo,” so they went ahead with the female embryo after consulting the couple and getting approved by a medical board.
The risk of mitochondrial DNA from a donor is small since the mitochondrion is only 37 genes, with the human genome containing about 20,000 to 25,000 genes in total, added Zukin.
Since the science is new and remains controversial, certain experts advise going slow on performing these experimental procedures.
“We would be extremely cautious,” said professor Adam Balen, who chairs the British Fertility Society and dubbed the procedure highly experimental.
Knowles prefers going slow since the one-off experiments — mostly done in remote areas and without randomized control trials and rigorous scientific techniques — make it difficult to gauge long-term results, such as how much viral DNA remains and how many generations it is passed to.