DNA Research Holds the Keys to Human History – but It's Being Weaponized by Politicians

As Netanyahu’s attempt to link the Philistines to the Palestinians show, DNA analysis of ancient humans is being harnessed for political purposes

Excavating at the Philistine cemetery in Ashkelon, Israel, 2016.
MENAHEM KAHANA/AFP

Prime Minister Benjamin Netanyahu’s Twitter account blew up in July in the wake of an extraordinary tweet: “A new study of DNA recovered from an ancient Philistine site in the Israeli city of Ashkelon confirms what we know from the Bible – that the origin of the Philistines is in southern Europe. ... The Palestinians’ connection to the Land of Israel is nothing compared to the 4,000 year connection that the Jewish people have with the land.”

Netanyahu, like the hundreds of people who replied to the tweet, interpreted the study as overwhelming proof of Jewish ownership of the Land of Israel and proof that the Philistines — who share an etymological history with the Palestinians — were “new” immigrants, having arrived here just 3,000 years ago. Officials from the Palestinian Authority were quick to say that Palestinians are the descendants not of the Philistines but rather of the Canaanite Jebusites, who were ostensibly the original inhabitants of the land.

Netanyahu’s tweet came a few days after the publication in the magazine Science advances of a study by researchers from Germany’s Max Planck Institute for the Science of Human History and the Leon Levy Expedition. The researchers sampled DNA from 10 skeletons found in Ashkelon and concluded that their gene pool came from southern Europe. The finding supports the accepted theory that the Philistines migrated from the area of Greece and settled along what is today Israel’s southern Mediterranean coast.

The study’s authors, however, were infuriated by the prime minister’s tweets. They considered responding but decided it might give the tweets more exposure. Netanyahu’s political spin on the research upset many scholars, who saw it as an example of the danger inherent in bringing genetics into the study of human history. Critics fear that used incautiously, genetic research not only has the potential to distort history but also can become a tool for racist propaganda in the hands of extremist politicians and groups.

The ability to extract and sequence DNA from samples that are thousands and even hundreds of thousands of years old has led to significant breakthroughs in the study of evolution. By sequencing Neanderthal genomes, scientists have learned about the health, physical appearance and settlement patterns of Neanderthals. Even more important, DNA research led to the discovery of formerly unknown hominids. The most famous being the Denisovans, which was discovered only thanks to a single finger bone found in a cave in Siberia, from which its owner’s genome was sequenced. The researchers were also able to determine that most modern human beings carry genes from Neanderthals, Denisovans and additional, as-yet unidentified hominids.

Portrait of a Siberian Denisovan woman produced based on her DNA sample extracted from her finger bone.
Maayan Harel/AP

Broad brush

These successes led researches to apply genetic tools to later periods, and according to some critics that is where the danger lies. A study published last week in Science Magazine of 4,000-year-old graves in southern Germany determined, using DNA and as well as the objects with which their occupants were buried that the wealthiest men were locals. Poor men, servants and most of the women came from elsewhere, and most of the high-status women were apparently sent to other communities. One can only manage the political conclusions that could be drawn from the study.

“The problem isn’t with the research itself,” says Raphael Greenberg, a professor of archaeology at Tel Aviv University. “Say I want to know about the connection between the Levant and the Greek region. I have various ways to examine it: pottery, inscriptions, symbols, language, and now something new has been added to my arsenal. That’s great, no one will deny that it’s useful. The problem is that DNA research has an element of magic to it. Only a few laboratories carry out these tests, at very high cost, and no one can argue with them,” Greenberg says. He adds that their operators don’t make do with presenting their findings; they go on to interpret the results. He believes that DNA researchers should leave conjectures about population migrations to the relevant experts.

The disagreement surrounding “Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past,” by Harvard geneticist David Reich, illustrates Greenberg’s argument. Reich is considered the most important researcher in the area of ancient DNA, but his critics attack him for reducing complex historical process into simplified sound bites. “He has lost some of the soul of what archaeology and sociology are,” wrote Anna Linderholm of Texas A&M University in a review published in Current Anthropology. “With his investigations he is painting with large brushstrokes a picture of our past, and in doing so, he might be missing some of the finer points. Who we are is much more than the genetics.”

Excavating at the Philistine cemetery in Ashkelon, Israel, 2016. Critics say genetic research could become an instrument for racist propaganda.
Gil Cohen-Magen

Critics argue that genetics alone cannot tell the complex story of the exchange of genetic material between two population groups, which involves not only migrations but also trade, war and the taking of male and female prisoners.

Gene sequencing, says Prof. Assaf Yasur-Landau of the University of Haifa, “is a completely new tool whose potential we don’t yet understand.... The danger is in making the connection between genetics and cultural. It’s absolutely forbidden and borders on racism.”

My granny was a Philistine

The dispute over the archaeological use of DNA is part of a broader discussion. Last year Reich published an opinion piece in The New York Times in which he argued that scientists should stop denying the existence of genetic differences between human population groups, rather than viewing race as entirely a social construct with no biological basis.

“It is important to face whatever science will reveal without prejudging the outcome and with the confidence that we can be mature enough to handle any findings. Arguing that no substantial differences among human populations are possible will only invite the racist misuse of genetics that we wish to avoid,” Reich wrote.

In an open letter produced by a group of 67 scientists and researchers and published on BuzzFeed, they attacked Reich’s approach and warned against returning to a racial-genetic understanding of humanity.

Archeologists excavating at the Philistine cemetery in Ashkelon, 2016.
Gil Cohen-Magen

“Human beings are 99.5% genetically identical.... [Y]ou could genotype all Red Sox fans and all Yankees fans and find that one group has a statistically significant higher frequency of a number of particular genetic variants than the other group.... This does not mean that Red Sox fans and Yankees fans are genetically distinct races,” they wrote.

Michal Feldman, an Israeli geneticist who works at the Max Planck Institute, was the lead author on the article on the skeletons from Ashkelon. “We’re trying to be cautious in our research and also in our press releases, and to explain exactly what we found,” she says. “We said we saw a genetic component that came from southern Europe, but that it disappeared after 200 years despite the fact that culturally they were still Philistines.” Feldman agrees that the genetics must be separated from culture. “There’s no such thing as a pure population or separate groups. Only a tiny part of the genome, 0.01 percent, attests to the origin, and most of the genes within that part are of no importance.”

Nimrod Marom, an archaeo-zoologist at the University of Haifa, says the danger is of “reducing the discussion to the question, ‘Where did your mother come from?’.” He says that DNA research is more interested in the origin of the Philistine’s grandmother than in the way he lived here. “In the end it doesn’t say much about me and doesn’t say much about anyone,” he says. “We get annoyed today when that’s done to us, when we are categorized according to where we came from, so there’s no reason not to be annoyed when it’s done to people from other periods.”

Greenberg also believes that the danger of reductionism in genetic studies is much greater than getting an inaccurate picture of the past. “We object to these classifications in our daily lives, we don’t want to be defined by something that we don’t see and have no control over. We want to say who we are by what we think and what we identify with. This method expropriates our identify from us. It says your identity isn’t your religion and it isn’t the food that you like, it’s what we tell you it is. There’s not really any such thing as the original inhabitants of this land.”