The Genetic Lottery: book review
It is perhaps a caricature to claim that conservatives think all inequality is genetic, so there is nothing we can do about it. It is probably less of a caricature to claim that liberals think no inequality is genetic, so all we have to worry about is environmental. At least one purpose of The Genetic Lottery by Kathryn Paige Harden, Professor of Psychology at the University of Texas at Austin, is apparently to convince liberals that people’s differing genetic inheritances may contribute to inequality (see also a profile of the author by Gideon Lewis-Krauss in The New Yorker).
I do not know why liberals and minority groups (they are overlapping sets) are afraid of research linking, for example, genes and intelligence, but I can guess along with Dr. Harden that it is related to their justifiable fear of eugenics. Comparing Dr. Harden’s work to eugenics is a bit like conflating nuclear power with nuclear bombs; it is right to be afraid of one, but not necessarily the other, and certainly not to be afraid of one because of the other.
Dr. Harden’s book is in two parts: “Taking Genetics Seriously” and “Taking Equality Seriously.” The first is a mostly scientific discussion of the relation between genes and various traits such as intelligence, which she claims partly determine your income and status. I found it a useful primer. The second part is more political and cries for mostly unspecified actions designed to increase the status of those who may be tacitly discriminated against because of a poor genetic inheritance.
After dispensing with the candidate-gene hypothesis (a single gene for a complex trait), Dr. Harden moves on to the genome-wide association study, or GWAS (pronounced gee-wass). The GWAS at first may sound like data dredging, but I think it is not. Rather, the GWAS samples the genomes of countless individuals and deduces which genes, and there are many, correlate with the trait in question. (They are actually single-nucleotide polymorphisms, or SNP’s, but never mind.) Researchers can then calculate a polygenic index for that trait in a given individual.
A person with a high polygenic index for height is apt to be tall, though not necessarily tall. Likewise, a person with low polygenic index for height is apt to be short, though not necessarily short. Dr. Harden claims that liberals have no trouble accepting these two statements, but will balk if we replace height with, for example, intelligence. She discusses intelligence (IQ) tests and acknowledges that early on they were instruments of eugenics but observes that IQ correlates, for example, with success in school, job performance, and even life span. She insists that we can reject eugenics without rejecting intelligence tests.
Importantly, she is at pains to point out that the vast majority of GWAS research has been carried out on people of White [her capitalization], European descent and cannot be used to demonstrate that one ethnic group may be higher in one trait than another, because different circumstances may cause different genes to correlate with a given trait, such as education. She is pretty convincing claiming that race, at least in the United States, is socially constructed, but frankly, as a Jewish male with a Jewish wife, I might under some conditions want to be screened for Tay-Sachs disease or cystic fibrosis.
I found the second part of the book interesting, but perhaps a little frustrating. Dr. Harden establishes that a high polygenic index for, say, education correlates with an advanced degree but that a low polygenic index does not preclude an advanced degree. Those who inherit a high polygenic index nevertheless are lucky and have won the “lottery” in the title of the book.
Dr. Harden argues, correctly in my judgment, that tracking in U.S. high schools may be part of what she calls a causal chain that mediates between genes and educational success. Students who get into the wrong track, perhaps in part because of their genes, may find certain options closed to them. The solution to this problem is difficult and cannot be found in genetics. Consequently, at one point she flirts with a kind of utilitarian solution whereby students are chosen by lottery; a lottery, even if carried out among students who are prescreened, runs the danger of punishing the most qualified. It is, nevertheless, not inconsistent with her claim that what genes you get are entirely a matter of luck, and I suppose that sometimes your luck might be bad.
I will not go into detail, but the author takes on Richard Herrnstein and Charles Murray, the authors of The Bell Curve, which she considers inegalitarian because they consider some traits to be better than others and people who hold those traits to be superior. On the flip side, she takes issue with Robert Plomin of King’s College London, who thinks that your genetic makeup is more decisive than she does. She also cites a number of philosophers, in particular John Rawls, and argues, with him, that the truly egalitarian society would look out for the least advantaged.
Incidentally, like the biologist and blogger Jerry Coyne, I was mildly bemused by her ducking the question of whether the universe is deterministic. Like Dr. Coyne, I think it is. That does not stop us from applying statistical methods to the study of gases or even the roll of the dice, both of which are deterministic. In the same way, I see no reason it should stop us from applying statistical methods to genetics.
Finally, I want to note that the book is well written and clear. The author draws effective analogies to illuminate her discussions, as when she compares calculating a polygenic index with rating restaurants in different cities. If all you look at is one spice (analogous to a single candidate gene), you will get a biased or wrong answer; you have to look at a variety of factors and quantify them.
I read the book on a Kindle, which was satisfactory except for some of the figures, for which I had to turn to my computer. When I put my editor’s hat on, I found little else to complain about. All in all, with my physicist’s hat and my editor’s hat stacked firmly one on top of the other, I can recommend the book wholeheartedly, though frankly the first part more so than the second.