Hannah Devlin Science correspondent 

Four radical new fertility treatments just a few years away from clinics

Synthetic embryos and three-person babies among advances revised fertility laws need to consider
  
  

Synthetic mice embryos being grown in a laboratory in Israel in August.
Embryos of synthetic mice being grown in a laboratory in Israel in August. Photograph: Ahmad Gharabli/AFP/Getty Images

The fertility watchdog is pushing for the biggest overhaul of fertility laws in 30 years and discussing how to “future proof” any new fertility laws to make sure they can deal with current and future radical scientific advances.

Here are four of the new reproductive treatments that scientists say could be just a few years away from the clinic.

Lab-grown eggs and sperm

Scientists are making significant advances in the ability to grow eggs and sperm in the laboratory. The ultimate goal is to take adult skin cells, transform them into “induced pluripotent stem cells” that have the ability to turn into other cell types and then, using a cocktail of chemicals, coax these cells along the developmental pathway to becoming either eggs or sperm cells.

This may sound biologically improbable, but scientists have already achieved the feat in mice, producing healthy pups. In theory, a female skin cell could be used to produce a sperm cell and vice versa, which would be revolutionary.

Translating this work into human cells is not straightforward. There are still big scientific hurdles to overcome, and demonstrating safety would be a lengthy process. But there is growing confidence that this will eventually be possible and already there are companies, such the US-based Conception, aiming to bring the most recent advances to the clinic.

Human genome editing

Genome editing is a method for making specific changes to the DNA of a cell or organism. Gene therapy, where new genes are added or faulty genes disabled in specific cells, is already used in medicine to treat genetic diseases.

Changing the DNA of an embryo goes a step further because the genetic changes would occur in every cell in the body, meaning the edits would be passed on to subsequent generations. The technique could allow people to avoid passing on heritable diseases.

However, in many cases, pre-implantation screening of embryos can achieve this goal and research has shown that gene editing tools risk producing “off target” changes. So there will be a very high bar for demonstrating that the technology is safe enough to be medically justified.

Three-person baby IVF

The last big amendment to UK fertility law came in 2015 when MPs voted for an amendment to allow a technique called mitochondrial transfer, designed to eliminate certain incurable genetic diseases. The technique involves swapping the egg’s mitochondrial DNA (a tiny fraction of the total DNA, which sits outside the egg’s nucleus) with that of a healthy donor.

At present, only two specific techniques are permitted, but many people would like the law made more flexible so that new techniques with the same objective could be licensed.

It is possible that in future the technique could have wider applications, for instance if faulty mitochondria were identified as a cause of infertility.

Synthetic embryos

UK fertility laws regulate the use of embryos in research, and place a 14-day limit on how far into development embryos can be cultivated in the lab. However, the HFEA has no remit over so-called synthetic embryos.

This month, two teams of scientists report creating these embryo-like structures, featuring a beating heart and primitive brain, from mouse cells. The synthetic embryos look essentially the same as “real” embryos but do not require an egg or sperm to produce. The same scientists are trying to replicate the work in human cells, and some think new legal guidelines are required.

Separately, many scientists would like to see the “14-day rule” relaxed to allow them to get a better understanding of human development, including why many pregnancies fail at an early stage.

 

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