Skip to content

Preimplantation Genetic Screening: One Step Closer to the Perfect Baby?

Prospective parents will be able to screen embryos for almost any known genetic disease using a revolutionary “universal test” developed by British scientists, led by Prof Alan Handyside 
The £1,500 test, called karyomapping, which should be available as early as next year, will allow couples at risk of passing on gene defects to conceive healthy children using IVF treatment.  The “genetic MoT” will transform the range of inherited disorders that can be detected. Currently only 2% of the 15,000 known genetic conditions can be detected in this way. Not only can it test for muscular dystrophy, cystic fibrosis and Huntington’s disease, but it can be used for testing for the risk of developing heart disease, cancer, diabetes and Alzheimer’s in later life.

Such Preimplantation Genetic Screening of embryos could be used not just to test for the genetic predisposition to disease, but also for genes which contribute to intelligence, personality type (neurotic, extroverted, etc), memory, impulse control, perfect pitch, and, in general, the genetic contribution to our physical and mental abilities, and disabilities.

I have argued that we have a moral obligation to select the embryo with the best chance of the best life. This brings us one step closer to being able to do that.

The HFEA currently limits genetic testing  to severe genetic disorders. But such limits are wrong and irrational. Imagine a couple have two embryos that are free of major genetic disorders. A has a 10% chance of Alzheimer Disease while B does not. What possible reason could there be NOT to select B? Why would we leave it to chance?

People will of course choose to select out first the worst conditions but why shouldn’t we have a child with no risk of Alzheimer Disease, rather than one with a risk, even if that risk is small. We should want our children to begin life with best genetic start.

People worry that this is a slide down a slope to creating designer babies, to testing for eye colour, height, mental and physical abilities. But we should embrace the selection of such non-disease traits, if they contribute to a child having better chance of a better life. Why wouldn’t we choose an embryo which will grow into a better ability at maths or music. Indeed, we should give our children the greatest range of gifts possible.

People worry that this is like the Nazis weeding out the weak and inferior. Or that it will result in a two tiered society of the genetically privileged and the genetically underprivileged, as in Gattaca.
But these fears are misplaced provided we focus on testing for genes that make our children’s lives go predictably better.

Nature has no mind to fairness or equality. Some people are born with horribly short genetic straws. Enabling couples to choose the best of the embryos will reduce natural inequality. And it is already relatively cheap. The cost of this kind of technology is falling exponentially. It will in the foreseeable future be as common as ultrasound in pregnancy.

Does this mean that we will create the perfect baby?

Firstly, with the current numbers of embryos available in IVF, we can only test for 2 or 3 conditions. You will have to choose between testing for risk of heart disease or hair colour. Parents should test for those conditions that have the greatest impact on their children’s wellbeing

However, in the foreseeable future, this barrier of embryo number (up to about 20) may be overcome. For example,  we could clone a woman’s skin cell, or genetically modify it directly  to produce stem cells. These stems could be used to produce eggs. In this way, we could produce by using stem cell technology hundreds of thousands of eggs from one skin cell from one woman. This would enable the production of hundreds of thousands of embryos and testing using this current technology for MANY MORE genetic conditions, including perhaps dispositions to mental and physical abilities.
Many steps in this process of producing egg from stem cells are complete in experiments in animals and raise many profound ethical issues. One of these is that, couple with Preimplantation Genetic Screening, we would select embryos from a couple that would be more genetically privileged than any they would have likely produced naturally.

Does this mean that we will be able to make the perfect baby? No. There are many other influences besides genes that determine how good our lives are. There maternal factors in pregnancy, the environmental  and familial and peer influences.  No matter how good the genetic start of our children is in life, they will never be perfect. And even if they were, life is risky and differences and deficiencies and disabilities would quickly emerge just as we lived life. We need not fear perfection. We will never have it. Selecting the best is far short of selecting the perfect.

Share on

1 Comment on this post

  1. “..But we should embrace the selection of such non-disease traits, if they contribute to a child having better chance of a better life. Why wouldn’t we choose an embryo which will grow into a better ability at maths or music. Indeed, we should give our children the greatest range of gifts possible….these fears are misplaced provided we focus on testing for genes that make our children’s lives go predictably better.”

    There may be something missing in the argument as it moves from ‘giving children the best chances’ to ‘selecting the best babies’. For example, a person may have a predictably better chance of getting a highly paid job in the UK if they have a lighter skin and European features. And of course a highly paid job may be part of what constitutes a better life. But it doesn’t seem that we should select out children who lack these features in order to give children in general a better chance in life. Rather, it seems that we should eliminate the racial prejudice that weights the chances against those with darker skins and African features. So it’s true that we should give children the greatest range of gifts and the best chances possible. But it’s not apparently true that the only way to do this is to select out those with whose chances are impaired by prevalent injustices such as racism.

    “Selecting the best is far short of selecting the perfect.”

    Perhaps we must first create a just world, if we are to be able to judge which are the best babies. It’s true that there will be no discrimination against disabled people, if there are no disabled people, and there will be no racism, if we are all of one race. But we will not have achieved justice or corrected any injustice, and these things are as valuable to us as music and maths.

Comments are closed.