Question: why are you allowed to use 3 parents? thanks

Laura Wales answered on 26 Jun 2015:

We haven’t carried out any treatments to create a baby using genetic material from 3 people but I don’t know what the future holds. It’s a very interesting question though.

This type of IVF treatment is used to prevent mitochondrial diseases which can be deadly or cause severe suffering in the baby born (if the pregnancy doesn’t end in miscarriage). The technique would be used if the mother could pass on faulty mitochondrial DNA to her baby (mitochondrial DNA is only passed on from the mother) and involves replacing the mother’s mitochondria with mitochondria from a donor so that a healthy embryo can develop. The baby would have the majority of its DNA from the mum and dad, but around 1% of mitochondrial DNA would be from the female donor.

It’s quite a controversial subject and some people think it will lead to genetic engineering of “designer babies” (at least that’s why it’s not available in the USA). However, this particular technique only involves mitochondrial DNA. Traits such as hair and eye colour, on the other hand, are controlled by DNA in the cell nucleus, so that wouldn’t be affected.

In the UK, reputable fertility clinics are licensed by the Human Fertilisation & Embryology Authority (HFEA) – they regulate everything the clinic does and they can take the licence away if the strict guidelines aren’t followed.