The Prindle Post
In the late 1990’s, doctors at the St. Barnabus Institute in New Jersey developed a groundbreaking new technique—they successfully produced a child using the genetic material of three different donor parents. The motivation for the innovation was to help certain at-risk couples have healthy biological children of their own. The procedure, if successful, blocks the spread of disease that is sometimes passed through mitochondrial DNA—a genetic contribution passed to children by their biological mothers. Some women pass on mitochondrial DNA that causes muscular dystrophy or respiratory problems. Leigh Syndrome, a fatal disease, is also passed through mitochondrial DNA.
Robison-Green, Rachel. "By Means of Human Selection: The Birth of Three Parent Babies". The Prindle Post. http://www.prindlepost.org/2016/10/three-parent-babies/