New York: The world's first baby using a controversial new technique employed by US scientists to include DNA from three parents in the embryo has been born.
'Spindle nuclear transfer' sees the mother's nuclear DNA combined with mitochondria from the egg donor. The nucleus is removed from the donor's egg and the nucleus from the mother's egg is inserted into it. The resulting egg is then fertilized with the father's sperm.
"The baby boy was born five months ago in Mexico to Jordanian parents, and is healthy and doing well," said media reports.
The boy's mother carried genes for a disorder known as Leigh Syndrome, a fatal nervous system disorder which she had passed on to her two previous children who both died of the disease.
She had also suffered four miscarriages.
The woman, whose identity has been withheld, and her husband sought the help of John Zhang, a doctor from the New Hope Fertility Center in New York City to have a baby that would be genetically related to them but would not carry the inherited disease.
The United States has not approved any three-parent method for fertility purposes, so Dr Zhang went to Mexico where he said that "there are no rules."
One method that has been approved in the United Kingdom, called pronuclear transfer, was deemed unacceptable to the couple because it would involve the destruction of two embryos.
Since the mother carried the genes for the disease in her mitochondria, or DNA that is passed down from the maternal side, Dr Zhang used her nuclear DNA and combined it with mitochondria from an egg donor, in a technique known as spindle nuclear transfer.
Medical team criticized for manner of announcement
Dr Zhang and his team are expected to describe their method at the American Society for Reproductive Medicine meeting in Salt Lake City, Utah, next month.
An abstract describing the research has been published in the journal Fertility and Sterility, but outside experts said much more remains to be understood about the research.
"As this technology is controversial and a world first, I think the investigators should have submitted a manuscript for full peer review instead of announcing these outcomes in this manner," said Justin St John, professor and Director of the Center for Genetic Diseases at Monash University.
Attempts began in the 1990s to create a baby by injecting mitochondrial DNA from a donor into the mother's egg, and adding sperm from her partner.
"Some of the babies went on to develop genetic disorders, and the technique was banned," the media report stated.
(With agency inputs)