It takes two to make a thing go right, and that generally includes human reproduction. But a new “three-person” baby is throwing social media into a tizzy, not just because “three person baby” is a killer name for a band but because the science behind it, and why it happened, may be key to reducing birth defects. In fact, in the future, a three-person baby might be the rule rather than the exception.
The baby in question was born to a Jordanian couple struggling with Leigh syndrome, a neurological disorder caused by damaged mitochondria in the egg. Leigh syndrome usually causes miscarriages. Mitochondria provide fuel for cells as well as regulate functions like cell death, and when someone is afflicted with Leigh syndrome the mitochondria refuse to provide energy for neural cells. Without the energy, the cells begin to die. The syndrome, which is passed down on the mother’s side and extremely rare, is essentially impossible to treat. The couple who volunteered for this procedure had experienced four miscarriages and, tragically, had had two children who died before the age of six.
What an American research team did was knock the syndrome out of the egg. They removed the nucleus of the mother’s egg, excising the damaged mitochondria, and placed it inside a donor egg, which was then fertilized. Essentially, it combined two eggs, although it’s not a fifty-fifty split, genetically speaking: The nucleus of the egg contains 99.9% of the genetic material; this three-person baby will only get 0.1% of their DNA from their donor.
Still, this does raise potentially troubling bioethical implications. Some people don’t like the idea of “designer” children at all, pointing out the possible issues of money turning even human genetics into a case of haves and have-nots. In fact, the procedure had to be done in Mexico since the US doesn’t allow this technique to be used at this time. Still, it’s unlikely this technique is going away, so expect more three-person babies in the future.
(Via The BBC)