Couples undergoing IVF treatment could be given the option to pick the “smartest” embryo within the next 10 years, a leading US scientist has predicted.
IVF：in vitro fertilization 体外受精联合胚胎移植技术，又称“试管婴儿”
Stephen Hsu, senior vice president for research at Michigan State University, said scientific advances mean it will soon be feasible to reliably rank embryos according to potential IQ, posing profound ethical questions for society about whether or not the technology should be adopted.
Hsu’s company, Genomic Prediction, already offers a test aimed at screening out embryos with abnormally low IQ to couples being treated at fertility clinics in the US.
“Accurate IQ predictors will be possible, if not the next five years, the next 10 years certainly,” Hsu told the Guardian. “I predict certain countries will adopt them.”
The prospect of a new generation of genetically selected babies has prompted concerns about unintended medical consequences and the potential for deepening existing social inequalities. The science underpinning the claim that intelligence can be meaningfully predicted by genetic tests is also contentious.
Peter Donnelly, a professor of statistical science at the University of Oxford, said any such IQ predictions should be treated with “huge caution”, adding: “I have grave misgivings about it on ethical grounds. I think it’s a really bad idea.”
Since the 1990s, couples undergoing IVF have been able to screen their embryos for mutations in single genes that cause serious diseases such as cystic fibrosis, as well as conditions like Down’s syndrome, caused by chromosome abnormalities.
Many other traits, including height, physical appearance, intelligence and disease susceptibility, are known to be partly heritable. But because the genetic component is spread thinly over hundreds or even thousands of DNA regions, it has previously been impossible to screen for these traits.
In the past decade, as vast genetic databases have been established, this picture has changed. Through analyzing many genes, each making a tiny contribution, it has been possible to calculate what are called polygenic risk scores, which give a person’s likelihood of getting a particular disease or having a certain trait.
Genomic Prediction is the first company to take embryo screening into this grey area of risk forecasting, offering to alert couples if an embryo has an “outlier” score for risk of cancers, diabetes, heart disease, dwarfism or low IQ.
Prediction for IQ is not good enough to give a reliable ranking, but Hsu said that knowing an embryo has a low score could still be desirable.
“Maybe the bottom 1% embryo will grow up to be a great person … even be a scientist, but the odds are against it,” he said. “I honestly feel if we can calculate that score and find a real negative outlier there’s an ethical responsibility for us to report that.”
The company projects that once high-quality genetic and academic achievement data from a million individuals becomes available, expected to be within five to 10 years, it will be able to predict IQ to within about 10 points.
Hsu is reticent about whether screening for high intelligence would be ethically justified, saying: “Let me just decline to answer that at the moment.”
In some countries, such as Singapore, there is likely to be a high level of public acceptance and demand for such tests, he suggested. “I think the overwhelming majority would say yes, absolutely, parents should be allowed to do that,” he said. “Before you write your piece, you might just want to think that a billion people on the other side of the world might have a different view.”
Whether such tests will become available in the UK would depend on approval from the Human Fertilization and Embryology Authority (HFEA).
“If the HFEA decides that it’s not right for the UK, I will respect that,” Hsu said, but predicted that “rich people from the UK will fly to Singapore” if they are unable to get the tests locally.
Some in the UK take the view that prospective parents have a right to access such tests. “I don’t think people should be deprived of that knowledge,” said Prof Simon Fishel, the founder of Care Fertility.
Fishel questioned whether there is any ethical difference between picking an embryo ranked highest for IQ or sending a child to a private school. “What’s wrong with ranking an embryo if you can rank a child?” he said. “I think there are plenty of people who’d choose embryo Oxford [rather] than embryo A-level failure.”
In practice, though, couples often have only a few embryos to choose from. And there are concerns about unintended consequences. For instance, there is some evidence linking higher polygenic scores for academic ability to higher likelihood of autism.
The technology is controversial, but that does not mean it will not gain acceptance in the future, Hsu said, drawing parallels with the reaction to IVF in its early days.
“The IVF pioneers … were called monsters, Frankenstein doctors; it was predicted that these babies would have health problems,” he said. “I am actually reassured by that. IVF is completely normalized now. Everyone who is pointing their finger at [Genomic Prediction] now should go back and read those articles.”