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Setting the scientific record straight on race, IQ, and success.
Armed with this knowledge, many investigators in the biological sciences have replaced the term “race” with the term “continental ancestry.” This in part reflects a rejection of “race” as a biological classification. Every so-called race has the same protein-coding genes, and there is no clear genetic dividing line that subdivides the human species. Another reason for using the term “continental ancestry” in lieu of “race” is improved precision for locating historical and geographic origins when we look at the genome. Thus, continental ancestry allows for more genetically accurate descriptors. For example, President Barack Obama was not just the first socially “black” president. He was also the first (as far as we know) who has European and African ancestry.
Genetic differences are a potential—but highly unlikely—explanation for national, racial, or ethnic differences in behavior and success.
In sum, racial categories now in use are based on a convoluted and often pernicious history, including much purposefully created misinformation.
It is a good time, then, to dispel some myths about genetic variation that have been promulgated by both the left and the right alike. On the left, many try to discredit the notion that genetic variation underlies group differences by pointing out that there is more genetic variation within these groups than between them. Another favorite approach is to cite the fact that all humans are 99.9 percent genetically identical and that no group of humans has a gene (i.e., a coded-for protein) that another group lacks. Both of these arguments are canards. After all, we are also 98-plus percent identical to chimps and 99.7 percent similar to Neanderthals. Oh, what a difference that 2 percent (or 0.3 percent) makes!
Simply stated: Overall genetic variation tells us less than specific differences that matter. Imagine a group of humans that had a mutation in the FOXP2 gene—often called the language gene—such that this transcription factor (a gene that helps stimulate the expression of select other genes) was nonfunctional. These humans would lack the ability to communicate through language. In fact, this gene’s significance was first discovered through the study of an English family in which half the members across three generations suffered from severe developmental verbal dyspraxia—they could not communicate orally. This family could be 99.9999 percent genetically identical to their neighbors, but what a huge difference that 0.00001 percent makes. This criticality of particular genetic differences, as opposed to global similarity, is not unique to humans. Through genetic manipulation of just four genes, scientists in the lab have been able to turn a mustard weed into a woody tree. It sounds like a genetic version of the 1970s game show, Name That Tune: In how few notes (or genes) can one radically alter the phenotype of an organism?
Highlighting the fact that all humans share the same genes ignores the fact that much of evolutionary change and biological difference is less about the development of novel proteins (i.e. genes) than it is about the regulation of those genes’ expression—that is, the extent, the timing, and the location of when and where they are turned on and off. In fact, when the Human Genome Project first began, the number of human protein-coding genes was anticipated to be on the order of 100,000. After all, we are certainly more complex than Zea mays (corn) with its 32,000 genes, are we not?1 As it turns out, we have a mere 20,000 genes (or fewer). So most human difference is driven by the turning on and off of those 20,000 genes in specific tissues at particular times. The same ones may be expressed in the brain and in the liver. They may get switched on by an attacking bacterium and silenced by a hot meal. Each one is like a multitasking parent balancing home and office…