Scientists finally revealed the world’s first baby who was born from DNA with three parents five months ago. While the couple’s identity remains anonymous, the mother was diagnosed with Leigh syndrome, which meant her DNA in the egg cells of her mitochondria suffered through mutations. This disease is a progressive loss of the ability to move and breathe.
All human cells have organelles, which are like organs within the cell. An important organelle is the mitochondria, and yes, it’s the powerhouse of the cell. This is what gives you energy for your body to move and function. Another important organelle is the nucleus, which contains DNA that is responsible for determining each individual’s characteristics. Mitochondria also contain DNA, which is passed down from parents to children.
For this couple from Jordan, the wife was unfortunate to produce kids because of her disease even though she was healthy. While this couple tried many times to have kids, both their previous children were also diagnosed with Leigh syndrome. The first baby died at six years and the second at eight months. While only a quarter of the mother’s mitochondria were mutated, the mitochondria randomly distributed in her eggs, so by chance, her children developed this dangerous disease.
After their losses, the couple wanted to see a fertility specialist. They were introduced to Dr. John Zhang, a medical director of the New Hope Fertility Center in New York. While Dr. Zhang attempted a spindle nuclear transfer back in 2003, his patient was not as successful when she had twins who were born prematurely and died, even though their mitochondria were normal.
At first the couple hesitated; they did not want to risk another life. But with much consideration, they decided to take the chance and try one more time.
One controversial issue about this procedure is that it is not legal in the U.S. This couple was sent to New Hope Fertility Center in Mexico to have the procedure completed. This technique involved three sets of DNA: one from the mother, one from the father and one from a healthy donor. Even though the ratio is 99.9 percent from the actual parents and 0.1 percent from the donor, the zygote would contain three different sets of DNA.
Dr. Zhang moved the nucleus of the egg cell from the mother into a healthy donor egg cell with its nucleus removed and healthy mitochondria. The egg went through in-vitro fertilization and was transplanted back into the mother’s uterus.
Within six months of the pregnancy, the mother could tell that this time would be different. The fetus showed healthy signs of activity by frequently kicking while her previous children were still for most of the time. The baby was born on April 6 and now is five months old, healthy and has normal mitochondria.
Many concerns arise with the fact that this procedure was performed outside of the U.S. since very few regulations are enforced in Mexico. There was no way of knowing if physicians were qualified and prepared for this technique, nor were there any records of previous successes in this technique. Although the baby is healthy now, it is important for him to have frequent check-ups to ensure that he is maintaining his health.
Several can argue that this method does not interfere with ethics, because it is the mitochondria that are being treated. While the mitochondria do contain DNA, only a tiny fraction is being treated and this controls the mitochondria. The DNA in the nucleus determines inherited traits of appearance and characteristics, or each individual’s phenotypes. Dr. McDonough-Stukey, who is a professor in the biology department at Hope College, mentioned that spindle nuclear transfer technique can be “very challenging to do without permanently damaging the egg.” However, this process can be viewed in the analogy of organ donations rather than “three parents.” Dr. McDonough-Stukey even mentioned the “mitochondria does impact the health of an individual, but there is no known connection to determining personality or appearance.”
Overall, as many as 12,000 women in the age range to bear children are diagnosed and 4,000 babies are born with this mitochondrial disease in the U.S. Spindle nuclear transfer may be a break through to remove the disease for a future family generation. This advancement in medical reproduction will improve survival rates from this disease. Philip Yeske, science officer for United Mitochondrial Foundation, even claimed that this provides the “opportunity to have a biologically related child without the disease.” Much more research has yet to be done, because of a “lack of long-term studies introducing a third genome, whether that has implications for that child.