November 21, 2019

expert reaction to a study looking at embryo selection based on traits like height or IQ

A study, published in Cell, has looked at the process of embryo selection based on traits like height or IQ.

Dr Liz Ormondroyd, Genetic Counsellor/Researcher, Radcliffe Department of Medicine, University of Oxford, said:

“It has long been feared that genetic information might be used to select embryos based on desire for characteristics such as increased height or intelligence. This computer simulation study shows that, for these complex characteristics, ‘designer babies’ remain in the realm of science fiction.”

Prof Dusko Ilic, Professor of Stem Cell Science, King’s College London (KCL), said:

“The power of willful ignorance cannot be overstated. There will always be people who believe in “designer babies” and that it is possible to select complex traits with a right approach or algorithm. Scientific evidence for warming of the climate system is unequivocal and many people still do not believe in climate change and they can be very passionate about it.”

Prof Joyce Harper, Professor in Human Genetics and Embryology, University College London (UCL), said:

“This study is a welcome addition to our current knowledge of how traits such as IQ and height are manifested. As this study confirms, traits such as height and IQ cannot reliably be detected using genetic testing. These are complex genetic traits that are also affected by the environment. This is reassuring, as the use of preimplantation genetic testing (PGT) technology for traits is controversial. At least one company is offering PGT for polygenic disorders, such as diabetes and heart disease – so called PGT-P.”

Prof Frances Flinter, Consultant of and Professor in Clinical Genetics, Guy’s and St Thomas’ NHS Foundation Trust, said:

“The idea that someone would put themselves through IVF and subject their embryos to the invasive procedure of biopsy, just in order to try and gain a couple of point of IQ, or a couple of cm in height, strikes me a bizarre. The authors correctly point out that height and IQ are the result of many factors, some of which are not even genetic.  Our ability to predict future height or IQ based purely on a few genetic variants is limited, particularly in non-Europeans, as demonstrated by the fact that the tallest children in families do not always have the variants most likely to be associated with increased height. The strict licensing regime for pre-implantation genetic diagnosis (IVF with embryo biopsy and genetic testing) in the UK protects us from the risk that PGD might be used for trivial reasons for which there is no solid scientific basis.”

‘Screening human embryos for polygenic traits has limited utility’ by Karavani et al. will be published in Cell at 16:00 UK time on Thursday 21^st November, which is also when the embargo will lift. 

DOI: http://dx.doi.org/10.1016/j.cell.2019.10.033

Declared interests

Dr Ormondroyd: “No conflicts.”

Prof Ilic: “I declare no conflict of interest”

Prof Harper: “No conflicts.”

Prof Flinter: “I review PGD licence applications for the HFEA”