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The future of dating and mating: OKCupid, meet 23andme
http://www.marketwatch.com/story/the...dme-2017-02-13
The art of mating has undergone many technologically induced changes from the liberation that young lovers found with the invention of the automobile to the swipe-right ease of matching on Tinder.
But another technology is afoot that few people know about but that will upend the way we match and reproduce in years to come: the polygenic score. This is a single number that sums up someone’s genetic potential—risk for disease such as diabetes or predicted height or even the genetic portion of her IQ.
OkCupid, meet 23andame.
With the spread of recreational genotyping through services like ancestry.com or 23andme, more and more Americans have learned some of what their DNA can tell them about their past (their ancestral origins) and their future, such as their risk for diseases like Alzheimer’s.
But while Americans have been mailing in their saliva samples in order to find out what proportion of their genome is descended from Neanderthals, or whether or not they are likely to have dry or wet earwax, scholars have been busy overcoming statistical obstacles to produce scores based on the entire set of a million or more bits of DNA that predict what we call “quantitative traits”—those that fall on a continuum, like body-mass index or verbal intelligence.
What does all this have to do with dating and mating? Well, now that a computer app can take the raw data of our Cs and Gs and Ts and As and spit out a single number—the polygenic score—that predicts (with error, of course) someone’s height or risk for cognitive decline, would you like to know whether the person who just proposed to you is a walking genetic time bomb?
We have always selected our mates for their phenotypes—outwardly observable characteristics—that are driven partly by genetics and partly by environment. Now that we can somewhat measure their genotypes—the actual stuff that a baby daddy passes on to junior—it is inevitable that discerning potential partners will demand their counterparts show their cards before committing. Even if you landed a man or woman with advanced degrees, would it give you pause if you learned that he or she was genetically likely to develop early dementia and, worse, pass that risk onto your offspring?
In research I have performed with colleagues, we find that we tend to match on observable traits like education and body-mass index, as we have to a degree for time eternal. That is, we are more likely to marry someone similar to us in these outward dimensions than if we hooked up by chance. We are doing this on a genetic level, too, as a byproduct of how we sort on health, social status and so on.
All this genetic sorting happens indirectly as we match on observed, outward characteristics. But what happens when it becomes as standard to share our polygenic scores with someone we are dating as it is now to talk about religious beliefs or desired number of children? Currently, the scores predict only with lots of error, but they are improving with each new iteration as scientists train them on ever larger samples of humans. Further, if suitors start actively screening potential partners on these scores, it almost doesn't matter how predictive they are of their respective outcomes, for a whole genetic sorting logic of its own may take over, generating a self-fulfilling prophesy.
What’s more, now that more and more couples are resorting to artificial reproductive technologies for baby-making, it is just a short hop to the world predicted by the 1997 dystopian movie “Gattaca,” where embryos are rated along a number of dimensions for their genetic potential before deciding which to implant.
There has been lots of big talk lately about the gene editing technology known as CRISPR. This allows scientists to swap out undesirable DNA for a custom-designed replacement sequence. While it holds great promise for addressing single gene diseases—think Huntington’s—it is probably less useful for addressing traits that are highly polygenic—meaning that the outcome is determined by myriad tiny effects spread across the entire genome.
As it turns out, polygenicity seems to be the rule, not the exception for most complex traits ranging from height to cognitive ability.
Rather than waiting for CRISPR to mature as a technology and then be refined for simultaneous use in thousands of locations in our chromosomes, it is much more likely that potential parents will merely screen their fertilized embryos to pick the “best” of the lot for implantation—whatever “best” means to that particular couple. The technology to do this is here today. No laws forbid it. It is just a matter of time before some rich and competitive parents-to-be find a fertility clinic willing to indulge their desires.
In five years, sperm and egg registries are likely to offer extensive genetic profiles along with the photos and descriptions of donor hobbies they now provide.
In 25 years, dating and mating are likely to look very little like they do today. Computer algorithms that calculate our genetic potential and sort potential mates like a medical-school match are likely to be the new yenta-bots.
Of course, we do not know all the unintended effects we may engender by selecting the genotypes of our offspring: might our efforts at maximizing, say, height and educational potential, result in a generation of social misfits?
We need to be careful as we step into this brave new world of reproduction: After all, phenotypes are for fun (i.e. hookups) but genotypes are forever.
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Originally Posted by Desperado
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