Explaining mitochondrial donation treatment: how a baby has three parents

Source: The post is based on the article “Explaining mitochondrial donation treatment: how a baby has three parents” published in The Hindu on 15th May 2023

What is the News?

A baby has been born in the UK using a technique called Mitochondrial Donation Treatment (MDT) (popularly called ‘Three Parents Baby’).

Why do parents go for Mitochondrial Donation Treatment (MDT)?

Mitochondria are basically the powerhouses of the cells. They generate energy and thus are also responsible for cell function in the human body. 

Certain defects might occur impacting the way the mitochondria produce energy for the cells (especially in the ‘energy-hungry’ tissues of the brain, nerves, muscles, kidneys, heart, liver), and thereby impacting cell function. The diseases that arise out of such mitochondrial mutations are called mitochondrial diseases. 

Some estimates put the incidence of mitochondrial diseases as one in 5,000 people.

Mitochondrial diseases are only passed on by the mother to their children.

In this case, the mother had mitochondrial disease, and she was intent on not passing it on to her baby. She also did not want to have a donor egg, for the baby would carry the genetic material of the donor.

So, they went for Mitochondrial Donation Treatment (MDT).

How does Mitochondrial Donation Treatment (MDT) work?

Firstly, through an advanced in vitro fertilisation technique, the baby’s biological father’s sperm was used to fertilize the eggs from the biological mother, who has mitochondrial disease and a third, female donor with clear mitochondria, separately.

Then, the nuclear genetic material from the donor’s egg is removed and replaced with the genetic material from the biological parents.

The final product — the egg — which has the genetic material (DNA) from the parents and the mitochondria from the female donor, is implanted in the uterus and carried to full term to yield a baby who will be free from the mother’s mitochondrial disease. This process is termed Mitochondrial Donation Treatment (MDT).

Are there any side effects to the MDT procedure?

Sometimes it is possible that a small amount of the maternal mitochondria with errors may get passed on during the procedure. However, more data is needed to establish consensus on this.