A.k.a “The social trends behind my most successful tweet to date”.

One week ago, I read this tweet by @hypervisible about Airbnb teaming up with 23andMe to “recommend heritage travel destinations” as follows:

“23andMe customers will soon be able to click through to their ancestral populations to find Airbnb Homes and Experiences located in their ancestral countries, and Airbnb now has dedicated pages that correspond with 23andMe’s genetic populations”.

I instinctively answered by “repeating” that tweet“in my own words, just to check I got it right”: “algorithm-enhanced self-segregation into new caste system is just one voluntary DNA check away."

Since that comment is, so far, my most popular tweet ever, I feel obliged to share that it didn’t come out of the blue. That comment comes from combining of some historical factoids with some digitally-enhanced trends I have already noticed online.

From English aristocracy to 21st century assortative mating

In 19th-century England, the rich almost exclusively mated among themselves. That, together with their money of course, is a reason why they were, among other things, “taller - a lot taller. In the age of 23andMe and Tinder, we are, borrowing a sentence from that article, “reproducing the same kind of division [that is, both economic and genetic] via a different set of dimensions.” Today for example we have, just like two or twenty centuries ago, rich people living much longer than poor ones: up to 20-years more in the USA.

Today, we also have Assortative mating, that is the tendency to “marry people like themselves, with similar education and earnings potential and the values and lifestyle that come with them."

But assortative making doesn’t look just for socioeconomical affinities. In this part of 21st century, we also have online dating which, by its own nature, triggers initial attraction mostly according to raw metrics. In the economy of heterosexual online dating, (declared!) height is immensely valuable. More specifically, it seems that people are “going out of their way to pair up” with “six inches of difference” in each couple. I also remember reading somewhere, but could not find the link, that average height difference inside couples has decreased since the arrival of online dating.

The result is that USA is becoming more (self) segregated (again: both economically and genetically, see above!), also thanks to dating apps and sites that make assortative mating much easier and invisible.

The same happens in non-western countries. In Pakistan, for example, “Muslim dating apps” make easier to find people “who have the same caste and religious beliefs”.

Summing up, people “Really Just Want to Date Themselves”: online dating makes that quest immensely easier, and the more data it gets, from whatever source, the more it works as expected. Whether that is healthy for society as a whole, it’s an entirely different matter.

So, if you wanted to know why I automatically replied that “algorithm-enhanced self-segregation into new caste system is just one voluntary DNA check away”, now you know why.

What you want to know anyway about genetics-based dating

1. The science of genetics-based dating is dubious at best: If you are LUCKY, that is
2. as @RealDaniel said: “participation” in such programs “isn’t even voluntary. If your relatives use 23andme or other DNA services, you can be interpolated as a datapoint."
3. Indeed, the chances that, thanks to “your stupid cousins feeding some commercial genomic database” that DNA can be used to profile YOU may already be sixty percent and rising,