Three-parent babies may soon undergo clinical trials by 2017, as successful test results have emerged.

Early last year, the UK became the first country to approve research and development on three-parent babies, which is possible through mitochondrial replacement therapy (MRT). The in-vitro fertilization technique prevents the mother's genetic disease to be passed on to the child by replacing the egg's "faulty" DNA with a healthy DNA from an egg of a different woman. This means that the babies will get genes from the father and two mothers.

Preclinical tests of a new method of mitochondrial donation or early pronuclear transfer have shown significant reduction in the number of faulty mitochondria in fertilized egg without limiting the capacity for onward development.

"Having overcome significant technical and biological challenges, we are optimistic that the technique we have developed will offer affected women the possibility of reducing the risk of transmitting mitochondrial DNA disease to their children," said lead researcher Mary Herbert from the Newcastle University Wellcome Trust Centre for Mitochondrial Research.

Study co-author and Centre for Mitochondrial Research Director Doug Turnbull said their research is an important step toward their goal of halting mitochondrial DNA disease transmission. Their study has put emphasis on the safety of the procedure.

"Embryos created by this technique have all the characteristics to lead to a pregnancy," said Turnbull. He added that their studies on stem cells included a cautionary disclosure that the technique may not completely prevent the disease transmission. Still, for women who are carriers of disease-causing mitochondrial DNA, Turnbull said "the risk is far less than conceiving naturally."

Regulators' Approval

For them to move forward with their study, the researchers will have to secure the approval of the Human Fertilisation and Embryology Authority (HFEA). Turnbull said they are looking to make the procedure available as a therapy for women by 2017. He added that they already have solid plans on how the study will unfold but these are all on hold as they are awaiting license from the proper authorities.

Turnbull admitted that they are already discussing the procedure with their potential patients and a good number of them are already considering the technique.

Ethical Issues

Before the UK granted approval for the research on three-parent babies, the procedure was met with much criticism. Some contend that the method somehow pre-programs the conception process and the lives of the children. Scientists, on the other hand, believe that such procedure removes the burden from families who suffer from genetic diseases.

While the UK is nearing its goal, the United States is still lagging with MRT research. Despite finding that MRTs are ethical, the Congress is not yet having it. The U.S. Food and Drug Administration said that the Congress prohibited them from having genetic modification of embryos.

The study was published in Nature on June 8.

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