It may be time to reenroll in high school health class, because a big change has just been implemented to the reproduction lesson: babies who have three genetic parents are now apparently a reality.
It has been announced that a medical team from the U.S. has delivered a baby boy—who is now healthy and five months old—with three sets of genes. The baby, who is the son of Jordanian parents, was delivered in Mexico where the controversial procedure, not yet legal in the U.S., could be carried out.The description for the revolutionary medical procedure, which comes via New Scientist, describes a process of combining an egg from the mother, an egg from a donor, and the father’s sperm. The nucleus from the donor’s egg is removed, discarded, and replaced with the nucleus from the mother’s egg. Then that new egg, with the donor’s mitochondrial DNA and the mother’s nuclear DNA, is fertilized with the father’s sperm (and thusly his nuclear DNA as well).
The procedure was executed in this case in the hopes of battling Leigh syndrome, a deadly disease that affects infants’ central nervous systems. While the mother involved in the three-parent procedure is healthy, she is a carrier of the genes for Leigh syndrome, and prior to the birth of this baby, had already lost two children to the disease.
Because the genes for Leigh syndrome reside in cells’ mitochondria, removing the mother’s mitochondrial DNA from the baby and replacing it with that of the donor’s, should hopefully eliminate the risk of the baby developing the disease. The medical team also chose a male embryo in order to ensure that the child won’t pass on the defective mitochondrial DNA in the future.
Zhang’s medical team has already tested the baby boy to see if he has the genes for Leigh syndrome. According to the results, only 1% of his mitochondria has it—it reportedly takes 18% of mitochondria to be affected for there to be a problem, so it seems that for now the team is cautiously optimistic. And though this baby is not the first instance of such gene editing, with every advancement in the process, the potential for eradicating life-threatening diseases decreases.
What do you think about this “three-parent” procedure? Are you excited to see the world of reproductive medicine evolve, or are you just thinking about Gattaca? Let us know your thoughts in the comments below!
Images: George Nakamura/Flickr