Banned in the 1990s because of its success rate, the infamous "three-parent" technique that uses DNA from three people makes a comeback when a baby boy born from Jordanian parents proves to be healthy. During the first trials of the study, the babies developed genetic disorders thus the banning.

According to New Scientist, the "three-parent" technique was studied and developed in hopes of allowing parents with genetic mutations to have a healthy child. In this case, the baby's mother has the gene for Leigh syndrome, a fatal infliction that attacks the young nervous system. The mother's first two children died of the syndrome at ages six and eight months. The couple has been trying to have a family for almost two decades.

In the continuous and excruciating search for a way to start a family, the couple consulted John Zhang of New Hope Fertility Center in New York City. At the time, Zhang was in the midst of studying and developing the "three-parent" technique and has found two ways to do it: pronuclear transfer and spindle nuclear transfer.

Because the first technique involved destroying the embryos by taking out the nucleus from a donor's fertilized egg and replacing it with the mother's, the couple insisted on the second technique. Zhang proceeded with the "three-parent" technique by removing the nucleus of the mother's egg and transferring it to the donor's egg that had its own nucleus removed. The result allowed the fertilized egg to have the nuclear DNA of the mother and the mitochondrial DNA from a donor thereby preventing the baby from inheriting the mitochondrial disease the mother carried.

The procedure is only legal in the United Kingdom and because of that, Zhang and his team had to do the procedure in Mexico.

"Without much ado, it appears the first mitochondrial donation baby was born three months ago. This was an ice-breaker. The baby is reportedly healthy," said stem cell scientist Dusko Ilic, as reported by The Guardian. Hopefully, this will tame the more zealous critics, accelerate the field, and we will witness soon the birth of the first mitochondrial donation baby in the UK."

Watch News Scientist's coverage here.