'Choosing not to look is not the same as not caring' – public attitudes to embryo selection

People's opinions on using preimplantation genetic testing (PGT) for non-medical traits do not always reflect the decisions they make about selecting embryos when presented with the results.

In a large study of more than 2000 people, an international group of researchers investigated whether members of the public want polygenic risk information, and whether having it would influence their embryo selection decisions. Results published in Nature Human Behaviour showed that although many people said they did not want embryo trait information, it affected their choices when they were presented with it.

'People are uneasy about asking for this kind of information, but they act on it once it is in front of them,' said Dr Edmond Awad of the University of Exeter and the Uehiro Oxford Institute, who led the study. 'Choosing not to look is not the same as not caring.'

The study recruited participants from the USA and China, representing two culturally distinct populations. Participants were presented with multiple dilemmas comparing two traits and simplified risk information based on polygenic score data. The study asked about two medical conditions: heart disease and visual impairment, and two non-medical traits: antisocial behaviour and low IQ.

The findings revealed a discrepancy between stated preferences and actual choices. In both cohorts, people were most willing to consider testing for heart disease risk, and significantly less so for low IQ, antisocial behaviour and visual impairment. On average, people were more willing to test for the two medical traits than the non-medical ones.

When asked about selecting between hypothetical pairs of embryos, respondents were most likely to avoid embryos with an increased risk of heart disease, but avoiding antisocial behaviour was a close second, followed by low IQ. Embryos with an above-average likelihood of visual impairment were chosen much more often than those with an increased chance of non-medical traits.

As a result, the authors cautioned against strict distinctions of 'medical' versus 'non-medical', as the study showed that participants based their decisions more on the perceived severity of potential consequences and, secondarily, the extent to which the attribute affects many areas of life.

UK regulation bans testing embryos for polygenic traits (known as PGT-P; see BioNews 1325), but PGT is permitted for a list of monogenic or chromosomal variants where 'there is a significant risk' that a person 'will have or develop a serious physical or mental disability, a serious illness or any other serious medical condition.'

'Regulation in this area rests on a category,' said senior author Professor Julian Savulescu from the University of Oxford. 'Our results suggest people do not think in categories when the choice is in front of them.'