The Human Fertilisation and Embryology Authority have conducted a scientific review of the use of three parent in vitro fertilization to prevent mitochondrial disorders after a request from the Secretary of State for Health.
The government may allow three parent reproduction if the scientific evidence is compelling enough for them.
What is Three Parent IVF?
Three parent IVF, also called mitochondrial transfer, is where an egg is taken from the mother, another egg from a donor and sperm from the father. The donor egg is then stripped of its DNA, except for the mitochondrial DNA and this is added to the mother’s egg to make a genetically altered, re-constituted egg that does not have a mitochondrial fault. It is then fertilized by the father’s sperm. Although any resulting child would have the majority of his DNA from his biological parents, but he would also have his mitochondrial DNA from the egg donor, effectively giving him ‘three parents’.
What is Mitochondrial Disorder?
Mitochondria are the energy stores within cells in the body. When they do not produce the amount of energy needed for the cells to operate, disease can occur. This is because of a variation in the mitochondrial DNA. Examples of disorders that can be caused are:
- Diabetes mellitus
- Vision problems, including blindness
- Deafness
- Encephalopathy
- Seizure disorders
- Neuropathies
- Mental retardation.
These are just a few of the medical problems that can be caused by mitochondrial dysfunction and they range from mild to life threatening.
Mitochondrial dysfunction is considered to be rare but this maybe because it was only discovered around 15 years ago so doctors and scientists are still learning about it. They have now discovered over 120 mutations in mitochondrial genes that can cause disease, particularly in children. However, children are not routinely tested so no one knows the true figures for how many people are affected by this disorder.
As its effects can result in severe disability and death, the medical community, including the Human Fertilisation and Embryology Authority (HFEA), are keen to use three parent IVF to prevent it from occurring.
Although pre-implantation genetic diagnosis (PGD) has been invented to screen for genetic disabilities by removing a cell sample from developing embryos and then only implanting those found to be healthy, it cannot screen for all mitochondrial conditions and as it is solely inherited from the mother (from a fault within her egg), even if a genetically normal girl is born as a result of PGD, she may pass on mitochondrial dysfunction to her children via mutations in her eggs.
The HFEA say that they have no evidence that the procedure is unsafe but that they would have to do further tests to make sure it was safe.
The ethics of bringing children into the world with three parents has not been discussed.
Sources:
- Scientific review of the safety and efficacy of methods to avoid mitochondrial disease through assisted conception, HFEA, April 2011.
- Mitochondrial Research Guild.
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact a doctor for advice.
Joanna Karpasea-Jones - I have been a health writer since 1997 when I published my own newsletter, SHOTS. I have written 2 books on childhood health, and write ...
