Born of Three: A New Frontier in Fertility

Scientists have achieved a breakthrough in IVF by using DNA from three individuals—a step that could eliminate certain inherited disorders.

In a major leap for reproductive medicine, researchers have successfully used DNA from three individuals to create healthy babies through In Vitro Fertilisation (IVF), opening up new possibilities for preventing inherited genetic disorders. Eight babies have been born in the UK using this technique, which remains in its early stages but is already being hailed as a potential game-changer in the field of fertility treatment.

This cutting-edge process—medically known as Mitochondrial Donation Treatment (MDT)—works by replacing faulty mitochondria in a mother’s egg with healthy ones from a female donor. It’s a highly targeted intervention that still allows the baby to inherit the nuclear DNA from its biological parents, while receiving only the mitochondrial DNA (a tiny fraction of genetic material) from the donor.

Until now, IVF procedures typically involved just the egg and sperm of the intending parents. However, this new approach enables scientists to eliminate serious mitochondrial defects, often responsible for life-threatening genetic diseases passed from mother to child.

How the Procedure Works

There are two primary forms of MDT:

1. Maternal Spindle Transfer (MST): The mother's genetic material is extracted and inserted into a donor egg containing healthy mitochondria but no nuclear DNA. The resulting egg is then fertilised with the father's sperm.

2. Pronuclear Transfer (PNT): The mother's and the donor's eggs are fertilised with the father's sperm. Then, the nuclear material from the donor's fertilised egg is removed and replaced with the nuclear material from the mother’s fertilised egg.

In both methods, the baby effectively has DNA from three people—mother, father, and the female donor—but the donor contributes only the mitochondrial DNA, which makes up less than 1% of total genetic material.

Why This Matters

Mitochondrial diseases are often passed down maternally and can lead to severe neurological and muscular disorders in children. Such illnesses occur in roughly one out of every 5,000–6,000 births and currently have no cure. With MDT, doctors may now be able to prevent such disorders at the embryonic stage, offering new hope to families with a history of genetic illnesses.

The UK’s Human Fertilisation and Embryology Authority (HFEA)—a leading regulatory body in Europe—has officially confirmed the success of these births. Experts believe the technology could be a beacon of hope for high-risk families, going far beyond traditional IVF by actively preventing inherited conditions.

Despite its promise, mitochondrial donation raises several ethical and legal questions. Since it involves direct genetic intervention in human embryos, some critics caution that the long-term effects are still unknown. The eight babies born so far are under medical observation to study any possible future implications.

Moreover, while the UK has established a legal framework for this technique, many countries—including India—still lack clear regulatory guidelines. The procedure is also considered highly expensive and remains inaccessible to most people.

What are mitochondria?

Mitochondria are tiny organelles within human cells responsible for generating energy. Defects in mitochondrial DNA can lead to serious health conditions, particularly affecting the brain, heart, and muscles.

Though still at an experimental stage, the successful use of three-person DNA IVF marks a new chapter in the field of reproductive science. As research progresses and ethical frameworks evolve, the technique may pave the way for a future where hereditary diseases no longer determine the fate of generations.

(The writer is a senior journalist based in Kolhapur.)