Become a fan of Slashdot on Facebook

 


Forgot your password?
Close
typodupeerror
×
Biotech Science

Humans Choose Friends With Similar DNA 204

Posted by Soulskill from the nice-to-meet-you,-pardon-the-cheek-swab dept.
KentuckyFC writes "The study of social networks has long shown that people tend to pick friends who are similar to them — birds of a feather stick together (PDF). Now a study of the genomes of almost 2000 Americans has found that those who are friends also share remarkable genetic similarities. 'Pairs of friends are, on average, as genetically similar to one another as fourth cousins,' the study concludes. By contrast, strangers share few genetic similarities. The result seems to confirm a 30-year-old theory that a person's genes causes them to seek out circumstances that are compatible with their phenotype. If that's the case, then people with similar genes should end up in similar environments and so be more likely to become friends."
This discussion has been archived. No new comments can be posted.

Humans Choose Friends With Similar DNA More

Humans Choose Friends With Similar DNA

Comments Filter:

  • How dare you!? (Score:5, Funny)

    by i kan reed ( 749298 ) on Friday September 06, 2013 @01:25PM (#44777361) Homepage Journal

    How dare you insult my friends by comparing them to me!

  • Similar areas? (Score:2, Interesting)

    by Anonymous Coward

    Was there a control for geographically similar area? If you live in certain areas like Appalachia, everyone you know is probably a fourth cousin. So of course your friends would be related to you.

  • Whatever the cause, the discovery that our friends are genetically similar to us has significant implications. “The subtle process of genetic sorting in human social relationships might have an important effect on a number of other biological and social processes,” say Christakis and Fowler.

    For example, germs, viruses and even information may spread more (or less) easily amongst groups that share a particular genetic background.

    So we evolved a tendency to monoculture, making us more vulnerable to disease? That would seem ... counterintuitive.

    • There are often trade offs in adaptations. Sickle cell animia isn't great, but having part of those genes wards off malaria. More vulnerable to disease, but having people who are like us around might lead to more social benefit. Like if a father dies, another man might take over if the children are similar to him.

    • Re: (Score:3)

      by TheCarp ( 96830 )

      > So we evolved a tendency to monoculture, making us more vulnerable to disease?
      > That would seem ... counterintuitive.

      Not really, only if taken out of context and to the extreme. The relation between friends is states as about the same as a "fourth cousin". A fair amount of mixing happens even amongst the children of a single pair of parents with 2 copies of up to 4 possibilites being selected for each gene in each individual... fourth cousins is still enough room for quite a bit of diversity.

      Think o

    • Re: (Score:2)

      by Valdrax ( 32670 )

      So we evolved a tendency to monoculture, making us more vulnerable to disease? That would seem ... counterintuitive.

      Actually, the study says the opposite. When it comes to immune system function, we strongly prefer people with different genes.

    • So we evolved a tendency to monoculture, making us more vulnerable to disease? That would seem ... counterintuitive.

      Not necessarily. It could be a simple side effect of our internal program that makes us social animals instead of solitary. So then perhaps the effect on disease vulnerability doesn't have a detrimental evolutionary effect greater than the evolutionary benefits of forming tribes.

    • So we evolved a tendency to monoculture, making us more vulnerable to disease?

      Monoculture? Hardly. Fourth cousins would, on average share 1/32 of their genes....

  • 2000 Wyoming (or Montana, or Nebraska) citizens (Score:3, Insightful)

    by rodrigoandrade ( 713371 ) on Friday September 06, 2013 @01:34PM (#44777465)

    I find this study to be extremely flawed, not to say elitist / racist.

    Yes, rednecks who listen to country music and drink cheap beer and whisky like to have friends who are also rednecks who listen to country music and drink cheap beer and whisky.

    If the study had been conducted with 2000 subjects from culturally diverse places, like NY or Tokyo, I'm sure the results would've been a lot diferent.

    I was going to post AC, but fuck it, I got karma to burn...

    • Re:2000 Wyoming (or Montana, or Nebraska) citizens (Score:5, Interesting)

      by Bill, Shooter of Bul ( 629286 ) on Friday September 06, 2013 @01:47PM (#44777645) Journal

      I find your comment to be the same. Assuming that people in the city are more sophisticated than "rednecks who listen to country music and drink cheap beer and whisky"? How is that not an elitist comment? Cultural bubbles can also exist within large urban areas. This is how you end up with a Little Italy, China Town, etc sections in each large city. There are others not so visually apparent, I'm just picking on commonly known ones who's existence I wouldn't have to argue about.

    • Re:2000 Wyoming (or Montana, or Nebraska) citizens (Score:5, Insightful)

      by cjc25 ( 1961486 ) on Friday September 06, 2013 @01:54PM (#44777741)

      I find this study to be extremely flawed, not to say elitist / racist.

      Yes, people who fit a stereotype of those I dislike like to have friends who are similar.

      If the study had been conducted with 2000 subjects from places with people like me, I'm sure the results would've been more comforting to me.

      FTFY

    • The data is from Framingham, Massachusetts. Where did you see any mention of the Midwest?

    • Re: (Score:2)

      by PRMan ( 959735 )
      But race is such a small part of DNA. At my last job, I had a friend who was from India. We just clicked immediately, no idea why. I'd be interested to see if his DNA is more similar to mine than other people I know in California. This is how I took the study.

    • Uh, I'm a software engineer working in Iowa on avionics. Embedded hardware that's part of an OBOGS unit. It let's fighter pilots breath. I was born in Omaha Nebraska. I'm part of the local hackerspace, founded a fencing salle, and regularly go to a symphony. Crown Royal and Maker's Mark is about the cheapest whiskey I'll stomach. I prefer rock and techno. I work with Indians and Chinese (and a lot of old white guys). I am, in short, "from the city". In Iowa. Deal with it.

      Damn straight you're burning karma.

    • Re: (Score:2)

      by khallow ( 566160 )

      If the study had been conducted with 2000 subjects from culturally diverse places, like NY or Tokyo, I'm sure the results would've been a lot diferent.

      It's worth noting here that the data used in the study comes not from Wyoming, but from the Framingham Heart Study [framinghamheartstudy.org] which apparently studies a few tens of thousands of people for cardiovascular disease over many decades. It's not a particularly ethnically diverse town so there's that going for you.

      Personally, I think we'd find that there are different distinct friend-acquiring strategies out there. Picking people like you is still probably going to be the dominant one no matter how diverse the area you pi

  • Could it be something more basic? (Score:5, Interesting)

    by lagomorpha2 ( 1376475 ) on Friday September 06, 2013 @01:35PM (#44777493)

    In a number of different memoirs from actors in the original Planet of the Apes, it was noted that people playing different types of apes always sat with each other at lunch. It was a bizarre granfalloon - baboons with baboons and orangs with orangs for no other reason than that they looked the same. And these were people that knew each other before the film.

    People have a natural inclination to like people that look more like them whether it makes sense in modern society or not.

    • But everyone wants those fine slim asians.

    • Re: (Score:3, Interesting)

      by moteyalpha ( 1228680 )
      That reflects something that I pondered. In terms of neural networks and the ability to recognize familiar things. The action of recognizing could be a composite of those people you have become familar with. In other words, a person could see someone and assign them for recognition by the similarity of their traits to others that are already impressed on their brain such that they would be 10 percent like my cousin, have a nose like my brother, walk ike my sister, etc. So in the same way that people communi

    • Comment removed (Score:4, Interesting)

      by account_deleted ( 4530225 ) on Friday September 06, 2013 @02:19PM (#44778039)
      Comment removed based on user account deletion

    • Re: (Score:2)

      by PRMan ( 959735 )
      And if you have ever seen "Hotel Rwanda", it appears that the Dutch can come in and start randomly classifying people and 50 years later they will go to war and start trying to genocide each other, even if they are from the same family.

    • Re: (Score:2)

      by MarkvW ( 1037596 )

      Maybe it goes deeper than looks! That would really be cool.

    • Re: (Score:2)

      by m00sh ( 2538182 )

      In a number of different memoirs from actors in the original Planet of the Apes, it was noted that people playing different types of apes always sat with each other at lunch. It was a bizarre granfalloon - baboons with baboons and orangs with orangs for no other reason than that they looked the same. And these were people that knew each other before the film.

      People have a natural inclination to like people that look more like them whether it makes sense in modern society or not.

      That doesn't make sense. A while ago, I had to with storing my clothes and getting dressed where there were no mirrors. I had no idea how badly I was mismatching clothes and colors.

      The point is I had no idea what I looked like. How would I seek out similar people?

      The different apes could have sat together for thousands of reasons. Something as small as a prelunch routine that gave the different apes even something small differently could result in them sitting together.

    • Re: (Score:2)

      by khallow ( 566160 )
      It's probably just that the people who worked together ate together.

      And granfallooning is a powerful mathematical technique. Surely, you've heard of the four granfalloon theorem [wikipedia.org]? Or the more general property of graph granfallooning [wikipedia.org]? And there's the topological result that one can decompose in non-overlapping granfalloons the sphere finitely in such a way that one can construct two identical copies by putting back together the granfalloons in different ways.

  • yeah, people like to live in a comfort zone — but i've found that some of the best friends come from right out of that comfort zone..

    2cents
    jp

    A man needs a little madness, or else he never dares to cut the rope and be free.
    (Nikos Kazantzakis, Zorba the Greek)

    • yeah, people like to live in a comfort zone — but i've found that some of the best friends come from right out of that comfort zone..

      What about people who have a mix of genes from all over? Does that explain the wide genetic diversity amongst my friends, and how I like to hang out in diverse places with not much racism?

      What is described here seems rather incestuous, like "all my friends are clones of me", like a bunch of Greys. I guess there are some people like that.

      • Re: (Score:3, Insightful)

        by Anonymous Coward

        I dont get how everyone on here keeps making the equation: genetics = race. Thats not what this is about.

        I'm an engineer. Since I was a kid, I've loved to take things apart and put them back together. The closest friends I have in life are all from different parts of the world but they tend to be like me in that they also grew up taking things apart and putting them back together. So whatever gene-grouping is responsible for that behavior is probably shared by my friends from India, Russia and Sweden.

        Geneti

  • It's normal. (Score:5, Funny)

    by nospam007 ( 722110 ) * on Friday September 06, 2013 @01:42PM (#44777591)

    After all, many friends fuck their friends' wives, so after a couple of generations, they are all a happy family.

    • They controlled for that:

      To eliminate the possibility that the results are influenced by people tending to make friends with distant relatives, we use only the 907 friend pairs where kinship <= 0 (recall that kinship can be less than zero whe n unrelated individuals tend to have negatively correlated genotypes). This procedure ensures that pairs of friends in the GWAS are not actually biologically related at all.

  • Fourth cousins? (Score:4, Interesting)

    by Tony Isaac ( 1301187 ) on Friday September 06, 2013 @01:43PM (#44777603) Homepage

    If there are only six degrees of separation between you and just about everybody on earth, the classification "fourth cousin" probably covers a large part of the earth's population!

    • Those are social degrees of separation [wikipedia.org], not ancestral.

    • Re: (Score:3, Informative)

      by alternativity ( 1617769 )
      Not really. The idea of six degrees of separation is based on acquaintance and not on genetic relations. E.g. think of China under the one child policy, if it continues, then each passing generation will lose a subsequent degree of cousins. The first cousins would disappear first, then second, third, fourth and so on, but six degrees of separation will still apply to them.

    • Re: (Score:3)

      by Kjella ( 173770 )

      You have a many more social connections than genetic connections. You only have two parents, being a fourth cousin means you share a great-great-great-grandfather and you have at most 2^5 = 32 of them or less if they've interbred. The world fertility rate is now on average 2.36 children, it'll be a rough approximation but each great-great-great-grandfather will have approximately 2.36^5 = ~73 descendants. That's ~32*~73 = ~2336 fourth cousins ignoring any overlap. Of course you'll have other close relatives

    • Back in my college Medieval History class, our instructor explained to us that the "Speak now, or forever hold your peace" line in wedding ceremonies has its roots in a Catholic church prohibition at the time which disallowed marriages between sixth cousins or closer. If you knew that the couple were more closely related than that, then you piped up right there and put the kibosh on the arrangement.

      But nearly everyone in England at that point was at least that closely related to each other, so the prohibit

    • I should have figured that everybody (in this crows) would jump on the technical distinction between "degrees of separation" and biological cousins. Well, DUH! I guess i need to spell it out. The point was, we all have an awful lot of fourth cousins!

  • ... such as birthplace and race?

    Race alone would account for a huge genetic difference, and people tend to be friends with people of their own race for all sorts of reasons that can be easily explained through psychology and sociology. You're also more likely to be at least distantly related to people who live in the same area as you do.

  • Slashdot just ran a story on universal genome sequencing at birth [slashdot.org]. How long before your prom date is set up before you're home from the maternity ward.

  • Choice of circumstance? (Score:5, Interesting)

    by fahrbot-bot ( 874524 ) on Friday September 06, 2013 @01:51PM (#44777705)

    I'm reminded of the Better Off Ted episode Get Happy [tvrage.com]

    Linda suggests that Veridian let its employees have decorations in their company. Veronica agrees, but the company selects the decorations and assigns them to the employees. Linda discovers that she's suddenly a cat person, while other employees have cars, Green Bay Packers, or space decorations.

    ... Linda bonds with her fellow cat employees who start obsessing about cats... At lunch, Linda decides to talk with the outer space employees. They think they're too smart for her, and the cat employees see her as a traitor... Later, Linda discovers that the cat people have destroyed her cat decorations.

    "Veridian Dynamics. Teamwork. It keeps our employees gruntled."

  • Do my asian friends not exist? Or am i not human? Or are asians and white people far more closely related on a genetic level than i've previously been led to believe?
  • I have only a few close friends. They're mixed races and ethnicity, so I'm obviously not going by phenotype. I think a lot of it is the demographics of the group more so than DNA.

  • More eugenics propaganda! (Score:3)

    by s.petry ( 762400 ) on Friday September 06, 2013 @02:08PM (#44777925)

    Nothing to see here, move along.

    I'm sure that a few will claim "no, you are just anti-science" or some such but lets check a simple fact. 2000 genes were used in this study. What percentage of the human genome is this? Not only would this mean that "correlation == causation", but that correlation of 8.024e-6 (yes, that is a very small number) is the "normal".

    • Re: (Score:2)

      by starless ( 60879 )

      2000 genes were used in this study. What percentage of the human genome is this?

      "A 2012 analysis of the human genome based on in vitro gene expression in multiple cell lines identified 20,687 protein-coding genes."
      http://en.wikipedia.org/wiki/Human_genome [wikipedia.org]

      • Re: (Score:2)

        by s.petry ( 762400 )
        Thanks for the correction. This makes the analysis on 8.024e-5 which is still a very small percentage of our genes.

        • Thanks for the correction. This makes the analysis on 8.024e-5 which is still a very small percentage of our genes.

          We share about 98% of our genes with chimpanzees, dude. It's not like any one of our many genes can be different, the vast majority are exactly the same. By contrast, the current theory that the homo sapiens first evolved in Africa is based on a study that looked at 1327 DNA markers. Are you going to claim that study is also flawed?

          • Re: (Score:2)

            by s.petry ( 762400 )

            Primarily, I am claiming that making psychological determinations by reviewing our DNA is a ludicrous prospect. Secondarily, claiming that we are 98% the same as chimpanzees is an absurd correlation used to dehumanize people, considering the length of DNA.

            While we can figure out certain mechanics, human behavior and knowledge are trained. They are not in our DNA.

  • This study fails on two counts: Americans are statistical outliers; the conclusion is fallacious due to poor understanding of causality.

    For those for whom this is TL;DR -- Americans are the worst possible population to base any form of human study on (let alone a flawed study) - ref Solomon Asch's conclusion. The short summary @ neuroecology [wordpress.com] ; the longer discussion @ pacific standard [psmag.com].

    Among Westerners, the data showed that Americans were often the most unusual, leading the researchers to conclude that

  • Does that mean I have canine DNA?

    Now you will have to excuse me - I have some territory to mark

    • Does that mean I have canine DNA?

      No, but if your relationship develops into something more serious than just friendship, maybe your joint offspring will . . .

  • A paper which suggests that fugly people usually date fugly people. lol

  • My best friend's a sponge - we share 70% of the same genes.

  • ... had to be posted by someone named Kentucky?

Slashdot Top Deals

If you aren't rich you should always look useful. -- Louis-Ferdinand Celine

Close