Genetically speaking, close friends more like distant cousins

Genetically speaking, close friends more like distant cousins

Apparently, we have a lot more in common with our friends than you might think. New research revealed that friends who are not related biologically are still similar to one another genetically.

Two researchers, who published their findings in the Proceedings of the National Academy of Sciences, examined nearly 2 million gene variation markers based on data from the Framingham Heart Study. From that data, they studied nearly 2,000 people and compared pairs of unrelated friends with pairs of unrelated strangers.

“Looking across the whole genome,” said study co-author Prof. James Fowler in a statement, “We have more DNA in common with the people we pick as friends than we do with strangers in the same population.” Fowler is professor of medical genetics at UC San Diego.

In fact, the researchers found that friends are as “related” in terms of genetics, as say fourth cousins or those who share great-great-great grandparents. That translates to about 1 percent of our genes, according to the research.

That 1 percent may seem small to the average person, but it’s a significant number in terms of genetics. “Most people don’t even know who their fourth cousins are,” said study co-author Prof. Nicholas Christakis. “Yet we are somehow, among a myriad of possibilities, managing to select as friends the people who resemble our kin,” explained Christakis, professor of sociology, evolutionary medicine and medicine at Yale University in New Haven, Conn.

Research also showed that genes found to be similar between friends appear to be evolving faster than others. Researchers suggested that the social environment itself acts as an evolutionary force.

“The paper also lends support to the view of human beings as ‘metagenomic,’ not only with respect to the microbes within us but also to the people who surround us,” said Christakis.

“It seems that our fitness depends not only on our own genetic constitutions, but also on the genetic constitutions of our friends,” he added.

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  1. Sarah Fitzpatrick July 18, 2014 at 10:38 am · Reply

    This is extremely interesting!

  2. What if your closest friends are people of other ethnicities? This study doesn’t seem to address that question–or at least the report doesn’t.

  3. There have been cases where people found out they were related to other ethnicities, so it still could be a possibility 🙂

  4. This makes a lot of sense. It explains why my best friend and I are so close:)

  5. Lynn Hutley

    This is quite fascinating.

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Aurora Health sites, which also includes freelance or intern writers.