As often happens with articles by the same author upon submission here, the article kindly submitted today has prompted some comments that may not take into account all the back-and-forth in the article. The article wraps up with,

"All this is suggestive and interesting, but not complete. To make a solid utilitarian case we would need to establish:

"What is the average IQ or general genetic quality of donors?

"What is the marginal increase in each offspring?

The comments posted here before I arrived in the discussion mostly relate to the first two issues. They make assumptions based on outdated popular literature that don't correctly estimate the likely return from the proposal. The genetics of human behavior is a topic I discuss every day with scientists who are members of the Behavior Genetics Association, including the association's current president, and it's a long, hard, uphill climb to help popular understanding of human genetics get connected with the latest research findings.

First of all, there is no good way to identify genes that may have a favorable effect on phenotype for IQ.

Chabris, C. F., Hebert, B. M., Benjamin, D. J., Beauchamp, J., Cesarini, D., van der Loos, M., ... & Laibson, D. (2012). Most reported genetic associations with general intelligence are probably false positives. Psychological Science.

http://coglab.wjh.harvard.edu/~cfc/Chabris2012a-FalsePositiv...

"At the time most of the results we attempted to replicate were obtained, candidate-gene studies of complex traits were commonplace in medical genetics research. Such studies are now rarely published in leading journals. Our results add IQ to the list of phenotypes that must be approached with great caution when considering published molecular genetic associations. In our view, excitement over the value of behavioral and molecular genetic studies in the social sciences should be tempered—as it has been in the medical sciences—by a recognition that, for complex phenotypes, individual common genetic variants of the sort assayed by SNP microarrays are likely to have very small effects.

"Associations of candidate genes with psychological traits and other traits studied in the social sciences should be viewed as tentative until they have been replicated in multiple large samples. Failing to exercise such caution may hamper scientific progress by allowing for the proliferation of potentially false results, which may then influence the research agendas of scientists who do not realize that the associations they take as a starting point for their efforts may not be real. And the dissemination of false results to the public may lead to incorrect perceptions about the state of knowledge in the field, especially knowledge concerning genetic variants that have been described as 'genes for' traits on the basis of unintentionally inflated estimates of effect size and statistical significance."

Second, whatever the calculated figure is for "heritability" of IQ by the classic twin study method or its modern refinements, heritability of IQ has nothing whatever to do with malleability (or, if you prefer this terminology, controllability) of human intelligence. That point has been made by the leading researchers on human behavior genetics in their recent articles that I frequently post in comments here on HN. It is a very common conceptual blunder, which should be corrected in any well edited genetics textbook, to confuse broad heritability estimates with statements about how malleable human traits are. The two concepts actually have no relationship at all. Highly heritable traits can be very malleable, and the other way around. In particular, a statement made in an earlier HN post

if everybody had the same genes, ~80% of the variation in intelligence would be eliminated

blatantly misunderstands what heritability figures show (besides also being wrong on the best estimate of the broad heritability of IQ). Here's a citation for a good review article on the subject that you can read online in full:

Johnson, Wendy; Turkheimer, Eric; Gottesman, Irving I.; Bouchard Jr., Thomas (2009). Beyond Heritability: Twin Studies in Behavioral Research. Current Directions in Psychological Science, 18, 4, 217-220

http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...

This review article includes the statement "Moreover, even highly heritable traits can be strongly manipulated by the environment, so heritability has little if anything to do with controllability. For example, height is on the order of 90% heritable, yet North and South Koreans, who come from the same genetic background, presently differ in average height by a full 6 inches (Pak, 2004; Schwekendiek, 2008)."

Another interesting review article,

Turkheimer, E. (2008, Spring). A better way to use twins for developmental research. LIFE Newsletter, 2, 1-5

http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...

admits the disappointment of behavioral genetics researchers.

"But back to the question: What does heritability mean? Almost everyone who has ever thought about heritability has reached a commonsense intuition about it: One way or another, heritability has to be some kind of index of how genetic a trait is. That intuition explains why so many thousands of heritability coefficients have been calculated over the years. Once the twin registries have been assembled, itӳ easy and fun, like having a genoscope you can point at one trait after another to take a reading of how genetic things are. Height? Very genetic. Intelligence? Pretty genetic. Schizophrenia? That looks pretty genetic too. Personality? Yep, that too. And over multiple studies and traits the heritabilities go up and down, providing the basis for nearly infinite Talmudic revisions of the grand theories of the heritability of things, perfect grist for the wheels of social science.

"Unfortunately, that fundamental intuition is wrong. Heritability isnӴ an index of how genetic a trait is. A great deal of time has been wasted in the effort of measuring the heritability of traits in the false expectation that somehow the genetic nature of psychological phenomena would be revealed. There are many reasons for making this strong statement, but the most important of them harkens back to the description of heritability as an effect size. An effect size of the R2 family is a standardized estimate of the proportion of the variance in one variable that is reduced when another variable is held constant statistically. In this case it is an estimate of how much the variance of a trait would be reduced if everyone were genetically identical. With a momentӳ thought you can see that the answer to the question of how much variance would be reduced if everyone was genetically identical depends crucially on how genetically different everyone was in the first place."

So we have no idea how to compare the trade-off between trying to influence people's IQs with shuffling different genes into them from the beginning of life versus influencing their IQs by improving their environments (at a critical stage of development? throughout life?) and we don't know which might have greater or more lasting effect.

Today, we can't even say that a person with a higher IQ than another person necessarily has better genes for IQ. The review article Johnson, W. (2010). Understanding the Genetics of Intelligence: Can Height Help? Can Corn Oil?. Current Directions in Psychological Science, 19(3), 177-182

http://apsychoserver.psych.arizona.edu/JJBAReprints/PSYC621/...

looks at some famous genetic experiments to show how little is explained by gene frequencies even in thoroughly studied populations defined by artificial selection.

"Together, however, the developmental natures of GCA and height, the likely influences of gene-environment correlations and interactions on their developmental processes, and the potential for genetic background and environmental circumstances to release previously unexpressed genetic variation suggest that very different combinations of genes may produce identical IQs or heights or levels of any other psychological trait. And the same genes may produce very different IQs and heights against different genetic backgrounds and in different environmental circumstances. This would be especially the case if height and GCA and other psychological traits are only single facets of multifaceted traits actually under more systematic genetic regulation, such as overall body size and balance between processing capacity and stimulus reactivity. Genetic influences on individual differences in psychological characteristics are real and important but are unlikely to be straightforward and deterministic. We will understand them best through investigation of their manifestation in biological and social developmental processes."

The new gene study for IQ going on in China, discussed in comments in this thread and on Hacker News this week, has just been responded to by the president of the Behavior Genetics Association.

http://ericturkheimer.blogspot.com/2013/02/steve-hsu-replied...