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PDF FormatMacedonian nationalists want Greece back, or at least its northern provinces. Their latest weapon is an obscure genetic study, which claims that while Macedonians belong to the older Mediterranean substratum of peoples, Greeks do not. Consequently, the study concludes, the Macedonians predate even the earliest Greek civilization.1 Among Macedonian political activists who believe that Greece “has held Macedonian territory illegally for… ninety-three years” and who dream of the re-unification of historical ethnic Macedonia, there is considerable excitement at the prospect of their view that Macedonians “are the oldest people living in the Balkans” being genetically corroborated.2 Welcome to the gene wars.
Genetically based claims to sovereignty are the newest tactics employed in old struggles over national sovereignty and borders.3 They are used to support assertions of historical primacy, the principle that the first of the nations still existing to have established collective life on a specific territory has a right to statehood there. The desire to claim historical primacy is so strong that national groups of recent origin and nations that arrived comparatively recently to the territory where they now demand sovereignty are inclined to invent histories alleging ancient roots. An example is the case of Ataturk, the founder of the Turkish Republic.
When Ataturk set about fashioning a Turkish nation from the ruins of the Ottoman Empire, he was confronted with the presence of the indigenous Greek and Armenian peoples of Anatolia, both of whom boast well-documented histories predating the Turkic speakers. The brutal ethnic cleansing and genocide by which Ataturk proceeded to eliminate these populations are well known, but less familiar is his re-writing of history in order to grant the Turks a claim to historical primacy. As Bernard Lewis explains, Ataturk’s narrative asserted that “the Turks were a white, Aryan people, originating in Central Asia… [who] migrated in waves to various parts of Asia and Africa, carrying the arts of civilization with them…. Sumerians and Hittites [an ancient Anatolian people]… were both Turkic peoples. Anatolia had thus been a Turkish land since antiquity.”4 And indeed, Ataturk’s remains lie in a grand Hittite-style mausoleum. Legal scholar Chaim Gans has also pointed out that the appeal of the historical primacy argument is such that national movements that were not, in fact, the oldest organized society on the territory where they claim sovereignty “do not try to deny the validity of the argument. What they do instead is construct a genealogy that supposedly demonstrates their kinship ties to extinct peoples who had occupied the disputed territories before their rivals.”5
For national movements that can demonstrate historical, linguistic, and archaeological evidence of primacy, such as the Basques, genetics are simply added to the list of determining factors when claiming rights to a given piece of land.6 But for national groups that lack these proofs, such as the Macedonians, justification must be sought elsewhere. Recently, they have turned to the field of genetics.
As its advocates maintain, genetics can be used to trace the descent of a population; in this, it offers an appearance of scientific certitude that is compelling to those who wish to bolster their claims to territorial sovereignty. But, as this essay will demonstrate, genetic data in truth offer virtually nothing to such groups: Much of the information being marshaled to support claims of national primacy is culled from studies that are either flawed or misinterpreted. Moreover, even when high-quality research does indicate a specific ancient people among a modern group’s ancestors, such data are not magic bullets that enable the group to confirm, scientifically, whichever assertion of ancestry it wishes to be true.7 Rather, as we will see, rights to territorial sovereignty are legitimately determined by a much more complex array of considerations. Put simply, fighting wars for territory using the rhetoric of genetics is bound to be a losing proposition.
Claims that genetic studies validate ethnic territorial aspirations cannot begin to be evaluated without some understanding of the science involved. How does one “prove,” for example, that Macedonians are more closely related to other Mediterranean peoples than are Greeks? The answer begins with the molecules that code our genetic endowment, called DNA. Chains of DNA are composed of four smaller molecules, strung together much like beads on a necklace, with each chain paired with a complementary string of DNA. The two strands are then woven together in a double helix. Each of the component molecules—called “bases,” and known by the first letters of their names as A, C, G, and T—has a regular partner in the opposing strand: A always pairs with T, and C with G.8 When cells reproduce, in order to insure that each daughter cell has a full complement of chromosomes, the DNA helices are replicated as well, each strand producing a matching strand by attracting the complementary molecules, A, C, G, or T.
Since all humans probably descend from a small number of common ancestors, we would all share identical, or near-identical, genetic endowments if DNA replication worked perfectly. Indeed, any two randomly chosen humans will have 99.9 percent of their DNA sequences in common.9 But because of imprecision in the replication process—that is, mutation—DNA patterns have diverged over time.
Now, if our DNA patterns simply differed randomly from everyone else’s, the first shot of the gene wars would never have been fired. But matters are not that simple: Patterns of mutation are passed down from parent to child, and among groups that are largely endogamous (that is, mating tends to occur within the group) those patterns may come to be widely shared. Particular DNA patterns are therefore more prevalent among some groups than others, and knowledge of these patterns has allowed researchers to map the genetic closeness of different ethnic communities.10 Moreover, since mutation rates tend to be constant over time, the degree of difference in DNA sequences between two ethnic groups yields a rough approximation of when they branched off from the common human tree, allowing scientists to trace migration patterns across the globe.11 These are precisely the studies that have been recruited to support claims of historical primacy.
Three levels of analysis are used in the study of intergroup genetic differences:12 The earliest studies did not look at DNA, but instead inferred differences in DNA patterns by looking at the products of particular genes, such as blood type. Frequencies of types A, B, and O differ systematically across the world, as is true for other markers found on cell surfaces, such as those associated with the immune system. More recent work has looked at the variant DNA sequences of particular genes—called alleles—in different population groups. But studying gene products or even the sequences of individual genes, although still in vogue in some places, turns out to be a crude method of determining genetic relatedness.13 Today, machines that rapidly sequence DNA strands have made it possible to look directly at the variations in DNA itself.
DNA sequences are usually compared in one of two ways.14 Variation at a single site among the three billion base pairs is called a SNP (pronounced “snip”). For example, if sequencing of DNA bases shows that most people have an A at a given locus, but the person being tested has a C, a SNP has been identified in that person’s genome. Examining variation in SNPs at dozens or even hundreds of loci in the genome allows the differences between two populations to be quantified. In the second way that DNA sequences are compared, researchers can examine groups of SNPs that tend to be inherited as a set, usually because they are close to each other on a particular chromosome. These sets are called haplotypes, and studies can explore their frequency across populations. Whether looking at SNPs or haplotypes, the larger the number of sites in the genome that are examined, the more reliable are the findings regarding the genetic closeness of the groups being studied.15
To understand who is winning or losing the gene wars, one other distinction is important: SNPs and haplotypes can be examined in the genome as a whole, or in only part of the genome. Two parts that can be uniquely informative are the Y chromosome and mitochondrial DNA. Since only men have a Y chromosome, and most of it tends to be passed down relatively unchanged from father to son, Y chromosome patterns can be used to track descent along the patrilineal line. The now-famous “Cohen haplotype” that is highly prevalent among male Jews who identify themselves as descendants of the biblical high priest Aaron is an example of such a Y chromosome haplotype.16 Similarly, mitochondrial DNA is separate from the rest of the genome and contained in mitochondria, which provide energy to the cells. Human mitochondria derive from the mitochondria in the maternal egg; both men and women inherit their mother’s mitochondrial DNA, but only women can pass their mitochondrial DNA to their offspring. Thus, examining mitochondrial DNA allows descent to be tracked through the maternal line. The recently announced finding that a large proportion of Ashkenazi Jews probably descended from as few as four women of Middle Eastern origin, for example, is the product of research on mitochondrial DNA patterns.17
