Thursday, November 13, 2008

I'll settle for imperfect

Breeding perfect babies

Prof. Julian Savulescu
Julian Savulescu

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 (AU$3,440) 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 has 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 genetic ally underprivileged, as in the film 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 two or three 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 use stem cell technology to produce 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, coupled 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 are 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.

2 comments:

Tigerlilycat said...

How HOT is Julian!!!!!! Does he donate sperm?? [ROFLMAO thinking about Nik's face if he reads this...]

Amani said...

LMAO ... you have the man who "shoots and scores!"