US study claims they can spot disease risk in IVF embryos…but experts insist it’s a waste of money

Genes linked to a dozen serious illnesses such as cancer, diabetes and heart disease can be detected in embryos, experts claimed today.  

The tests, if proven to be accurate, could be used by couples undergoing IVF to pick the healthiest children. 

And there are fears the technology could go on to be used to help pick out desirable traits, such as height and intelligence, in ‘designer babies’.

But independent scientists today called for caution over the findings, saying that any such test would be a waste of money because they cannot definitively prove that an embryo will go on to develop an illness.  

For the study in Nature Medicine, Californian-based firm MyOme analysed the genes of 110 embryos taken from 10 couples who underwent IVF.  

A more in-depth DNA analysis was also carried out on the parents, allowing the team to predict the genetic make-up of embryos. 

MyOme researchers were able to check if their projection was accurate — by taking samples from 10 embryos that were eventually used in IVF cycles and went on to be born. 

Results showed the children born had almost exactly the same genetic make-up as the team expected, with the predictions up to 99 per cent accurate. 

The genomes were analysed at sections of DNA used to produce a ‘polygenic risk score’, Nature reports.

Professor Dusko Ilic, an expert in stem cell science from King’s College London, said: ‘For future parents the proposed testing might sound seductive.

‘And they could easily be tempted to spend extra cash to assure that their child lives a healthier life. However, the money would be wasted.’

Polygenic risk testing differs from preimplantation genetic diagnosis (PGD), which is legal in the UK. 

PGD is used to screen for roughly 500 diseases that have a single gene mutation that triggers them, such as cystic fibrosis.

But illnesses linked with DNA quirks are usually caused by multiple genes, which can also affect other areas of the body in different ways. Both lifestyle and environmental factors can also raise the risk of various diseases.

Polygenic risk scores are not currently available on the NHS, but their legal status in private clinics remains murky. 

Experts have repeatedly urged British couples seeking IVF treatment not to be lured across the Atlantic for the costly treatments. The screening can cost around £1,000 for a single test.

Professor Ilic argued the study was more robust than others which have touted the use of PRS to screen for disease in embryos.

But he said the fundamental problem is that the score only indicates the potential for disease, not a certainty.

‘None of the predictions can actually exclude disease and guarantee that a child will remain free of these medical conditions,’ he added. ‘So, what is the point?’    

Dr Francesca Forzano, an expert in genetics Guy’s and St Thomas’ NHS Foundation Trust, said the study was full of unanswered questions.

He highlighted how the authors did not list the genes analysed, nor the sex of the embryos tested — a key factor for some diseases like breast and prostate cancers. 

‘The data presented, as well as the conclusions, are incomplete and need further clarification,’ he said. 

Dr Forzano also accused the researchers of ‘passing the buck’ when it came to the potential ethical problems. 

‘The most important issue – the ethics of the practice – is glossed over and dismissed as something to be handled in a counselling session with a medical geneticist,’ he said. 

‘This is major buck passing. A session of genetic counselling does not equate to an endorsement of any test, particularly one which is inappropriate.’ 

Professor Ewan Birney, deputy director general of the European Molecular Biology Laboratory said the idea of using PRS for embryos made him ‘uncomfortable’. 

‘As a citizen I am uncomfortable about a wide set of traits that could be considered in polygenic risk scores and I don’t think society is well served by allowing parents apparent control over these aspects,’ he said. 

Professor Alastair Sutcliffe, an expert in paediatrics at University College London, added PRS scores for embryos may lead to unintended consequences as families traumatised by certain diseases in their history look to exclude them at all costs.   

‘It’s possible that other polygenic conditions not looked at could have a higher prevalence in the residual embryos, a law of unintended consequences,’ he said.   

‘When a family is traumatised by a strong family risk of X (e.g. breast cancer) they will focus on that potentially irrationally and thus counselling will simply wash over.’