Post: #1

Spouses Tend To Have Similar DNA




What attracted you to your spouse? His eyes? Her laugh? Does he quote Tolkien in her sleep, just like you? Did you meet at your microbiology club in college? What if one level of similarity and attraction went deeper than that, say, down to the cellular level? A new study from the University of Colorado-Boulder has shown that spouses tend to have DNA that is more similar to one another than to a different randomly selected person. The results of the study have been published in the Proceedings of the National Academy of Sciences.

The researchers utilized 825 couples who were non-Hispanic white Americans. Each participant’s genome was compared to their spouse and then to two other people who were randomly selected. Altogether, the study compared about 1.7 million single nucleotide polymorphisms (SNPs). Couples were more likely to be similar to one another than to the people with whom they were randomly paired.

“It’s well known that people marry folks who are like them,” lead author Benjamin Domingue said in a press release. “But there’s been a question about whether we mate at random with respect to genetics.”

When population genetics assumptions are made, a very common one is that mating is random. We know this isn't entirely true, as people generally have a criteria which they use when finding a mate. Further understanding mating pairs on a genetic level will help refine the models used by scientists, allowing for more accurate predictions. However, researchers are also very familiar with nonrandom, assortative mating where traits like education and economic background are concerned. In short, two custodians could be very happy together, and two lawyers could be very happy together, but it is much less likely that a custodian and a lawyer would be happy together due to the vast difference in education and income. (Please do not get offended. There’s absolutely nothing wrong with being a lawyer, if that’s how someone chooses to live his or her life.)

The researchers have noted that based on this study, this “genetic assortative mating” explains about 10% of educational assortative mating. While genetics appear to be a factor in mate choice, it is a small one.

Of course, this study doesn’t definitively prove much of anything in itself, but it does set the stage for a wealth of follow-up study, including exploring if people choose friends based on DNA as well. In 2012, it was reported that 1 in 12 marriages were of people of different ethnicities, which would likely alter the results about choosing a partner based on similar DNA. The researchers will need to expand their scope to include participants more representative of America’s diversity in the future. Analyzing the SNPs could also provide more clues about which traits humans use in choosing relationships, either romantic or plutonic.

Read more at http://www.iflscience.com/health-and-med...V9ADY77.99

Post: #2

When I was reading about Meyer-Briggs Type Indicator, one source said that most of what determines a lasting marriage is already in our genes. That is because so much of your temperament is nascent.

I'm an INTP and I know I don't vibe well with ESF type women.

Post: #3

But how does it explain the tremendous divorce rate? One would expect similar DNA to put a damper on it, at least.

Post: #4

Might explain why couples who have being married a long time tend to look like siblings.

Post: #5

(05-21-2014 02:54 PM)Handsome Creepy Eel Wrote:  But how does it explain the tremendous divorce rate? One would expect similar DNA to put a damper on it, at least.

In the US and England, divorce rates have actually been falling since the 80s.

http://www.cnn.com/2011/LIVING/05/19/div...ates.drop/

http://www.theguardian.com/news/datablog...rriage-ons

The general consensus is that people are waiting longer to get married, but making better decisions about who they actually marry.

Post: #6

I believe we typically are attracted to those who share similar facial features but we also look for people with different immune systems to ensure a more defensive offspring.

http://www.theguardian.com/lifeandstyle/...ct-partner

Quote:Wedekind's results appeared to show that the women preferred the T-shirts worn by men with different compatibility genes from themselves, raising the possibility that we unconsciously select mates who would put our offspring at some genetic advantage. The experiment was controversial, but it did alter scientific thinking about compatibility genes.

I've seen this test done several times and they always pick the shirts that have different MHC.

Post: #7

Quote:The researchers utilized 825 couples who were non-Hispanic white Americans.

I wonder how strong the results would have been if they didn't artificially narrow down the population. Would the (relatively) large number of interracial couples in the US completely destroy the relationship they found?

Post: #8

I read up quite a lot about this some years ago. From what I remember the consensus was that, biologically, there are both advantages and disadvantages to offspring of close genetic matches. The disadvantages (due mostly to having the same recessive genes for "poor' traits) are well known. But there are also advantages. Apart from recessive genes for "good" traits, also a big drop in miscarriages in couples who have somewhat similar DNA. The conclusions was that the "ideal" level of relatedness, for purposes of having healthy children, was around 3 rd 1/2 cousins (I know you can't have a 1/2 cousin). This conclusion seems to fly in the face of the "hybrid vigour" theory, and it seems to get quite complicated. What I took away was that there are both advantages and disadvantages to having similar DNA to your spouse/other parent of your children. In attraction terms this would lead to a kind of push/pull, where people are both attracted to and repulsed by similarities to potential mates. They are most likely to be attracted to the person who maximises the difference.

Post: #9

(05-22-2014 03:48 AM)ElBorrachoInfamoso Wrote:  

Quote:The researchers utilized 825 couples who were non-Hispanic white Americans.

I wonder how strong the results would have been if they didn't artificially narrow down the population. Would the (relatively) large number of interracial couples in the US completely destroy the relationship they found?

Not to mention, Caucasians were known for inbreeding for a long time, so it could be part of a evolutionary thing to select similar looking Caucasian features...ofcourse the " similar DNA" theory could have come first..."chicken or the egg" scenario