The world’s first three-parent baby boy was born in Mexico to a Jordanian couple with the help a controversial new fertility technique that incorporates DNA from three people in the embryo.
The ‘three-parent’ technique also known as Mitochondrial donation (Mitochondrial Replacement Therapy) allows parents with rare genetic mutations to have healthy babies.
What is the case?
- The boy’s mother was carrying genes for Leigh syndrome, a fatal genetic disorder that affects the brain, muscles and nerves of developing infants.
- Genes for the genetic disease reside in DNA in the mitochondria (powerhouse of the cell), which provide energy for our cells.
- In this case spindle nuclear transfer was used to remove the faulty nucleus from one of the mother’s eggs and inserted it into a donor egg that had its own nucleus removed.
- The resulting egg with nuclear DNA from the mother and mitochondrial DNA from a donor – was then fertilised with the father’s sperm to create embryos.
- This embryo was implanted in the mother and the child was born nine months later in April 2016.
- Researchers have tested the boy’s mitochondria and found it contains less than 1% mutation.
What is Mitochondrial Replacement Therapy (MRT)
- MRT or Mitochondrial donation is a medical technique in which defective mitochondria carried by a woman is replaced with the healthy mitochondria of a donor.
- Through invitro fertilization technique (IVF), the egg is then fertilised with the partner’s sperm. Thus the embryo remains free from any such defects.
- The two most common techniques in mitochondrial donation are maternal spindle transfer and pronuclear transfer.
- Thus this medical technique prevents the transmission of mitochondrial (genetic) disease from one generation to the next.
- MRT proposes to give parents chance of having a child that is over 99% genetically matched to them and most importantly free of the mitochondrial disease.