I said-
In the near future, we might be able to routinely sequence the genome of any unborn child shortly after conceptionBut I didn't realize that this may be really very near indeed. Two recent reports have shown that it's possible to sequence fetal DNA from a maternal blood sample. In one case it was used to diagnose a 35 week fetus with a genetic deletion on chromosome 12 seemingly associated with autism, developmental delay and shortness.
This is big. Currently, the main way to get fetal DNA is through amniocentesis, i.e. inserting a needle into the womb. It's a substantial and not entirely safe medical procedure. A blood sample would be an order of magnitude cheaper and safer, but most of all it would be something you could do at home.
No longer would you need to go to a hospital and discuss everything with a doctor. You could take some blood, send it off anonymously to a sequencing company, and get the results in an email. It would take it out of the hands of professionals and open up a space for individual choice.
The cost of whole-genome sequencing has been falling exponentially and many think it will fall below the $1000 mark within a few years. Combine that with fetal DNA testing and we might see moderately well-off parents able to sequence fetal DNA within the next decade.
When this happens I think the personal genomics industry will suddenly become extremely "hot". At the moment you can sequence your own DNA for a few thousand $ if you want. The results may be interesting but they're of little obvious use. Whatever your genes are, you're stuck with them.
But as soon as we're talking about potential human genomes, it'll kick things up a notch. Media interest and political controversy is sure to follow. Personally I think it'll the debate will begin in earnest when we start seeing selective abortions on the basis of genes for "normal" variants rather than "disease" genes.
It's one thing to not want a child with blindness, or a high risk of leukaemia. But as a society I don't think we're ready for not wanting a child because they're predicted to be a B student rather than an A student, or brunette rather than blonde. At some point soon, though, we'll have to decide what we think about that.
Peters D, Chu T, Yatsenko SA, Hendrix N, Hogge WA, Surti U, Bunce K, Dunkel M, Shaw P & Rajkovic A (2011). Noninvasive prenatal diagnosis of a fetal microdeletion syndrome. The New England journal of medicine, 365 (19), 1847-8 PMID: 22070496
Srebniak M, Boter M, Oudesluijs G, Joosten M, Govaerts L, Van Opstal D, & Galjaard RJ (2011). Application of SNP array for rapid prenatal diagnosis: implementation, genetic counselling and diagnostic flow. European journal of human genetics : EJHG, 19 (12), 1230-7 PMID: 21694736
8 comments:
I think there's a bit of a leap in your final paragraph. While we know a fair number of alleles that increase the risk substantially of certain diseases, we don't know enough about the correlations of others with behavioural traits and abilities. People seem to forget that genotype is not phenotype and that environment is a massive onfluence on the latter.
However, I fully expect some unscrupulous or naive (hello 23andme) personal genomics companies to oversell the predictive value of genomics in the future and for their to be a cottage industry of genetics pundits writing newspaper article exposing this nonsense...
Yeah, I agree that predicting phenotype is very complicated, but there will be no shortage of people who claim to be able to do it.
actually I'm pretty sure that when this kicks off, the "early adopters" will be quacks and charlatans out for a quick buck, because all the real scientists will know that they can't predict more than 5% of variation in whatever trait it is.
But that will be enough to kick off the moral debate. And we do need to have that debate, eventually.
I should point out that we don't actually do "whole-genome sequencing" at this point, for any cost. There are regions of the genome which are very difficult to sequence (e.g. near centromeres), and all of the commercial sequencing platforms have systematic errors, which greatly increase the false positive mutation rate. Undoubtedly we can still catch plenty of real mutations, but one very scary possibility is that we might see parents, in the absence of professional consultation, deciding to terminate a pregnancy based upon a false positive identification of a mutation in a developing embryo.
Oh, I don't think we'll have to decide what we think about people not wanting a child on the basis of predicted academic potential or hair color or any such thing. People will go ahead and do whatever the law allows, regardless of what we happen to think about their decisions.
Now, should we want to try to work out what should be allowed and disallowed by law while continuing to respect precedent, civil rights, confidentiality, personal autonomy, and whatever folks' various spiritual guidance organizations have to say about the subject-- well, that's going to be... interesting.
What really worries me about this is the insurance companies. I know in Europe it's different, but here in the US insurance companies have the right to refuse coverage. Once personal genomics will be standard, will they refuse coverage based on risk alleles?
Well if we can preview the risk of a child becoming a politician i guess that goes a long to balance out all the negatives.
"People will go ahead and do whatever the law allows" said Stefan Zielinski
Organ donation transplant trafficking and illegal abortion do exist.
Illegal screening and selective abortion for male sex preference do exist at a spectacular scale.As well as infanticide of baby girls.
With cheap travels, the internet and human nature I think neuroskeptic is right to do its bit to make us think about the problem.
"regardless of what we happen to think about their decisions."said he.
Sadly, Stephan very few of us reach that independance of spirit.
Stephan: People will certainly do whatever the law allows - my question is really about what the law should allow.
But actually, it will be hard to police this. You could, say, make it illegal to decide to abort on the basis of fetal DNA tests (maybe with an exception for a defined list of "serious" diseases - but I wouldn't want to be on the panel tasked with drawing that list up).
But even if you did, there'd be nothing to stop people getting the DNA tested on the sly and then deciding to have an abortion "for an unrelated reason".
Unless you banned personal genomics entirely.
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