The section Unlike height, no one knows what IQ is actually measuring, buried deep in the article, is really all that's needed. "Height" is a well-behaved non-changing property that is meaningful, "IQ" is none of these things. Some fun facts:

- The variation between IQ tests done by the same individual is significantly higher than almost any reasonable cross-group variation (men vs. woman, country A vs. country B, doctors vs. craftsmen, ...)

- The original IQ-test had to use a mathematical trick to cut off "growth of intelligence" at exactly 16 years old, which totally incidentally was the age where mandatory schooling ended for the relevant population.

- The famous "Termites" study which attempted to use IQ to predict the future upper crust of society by testing a large number of children failed to predict any Nobel price winners, but excluded two future Nobel winners (they were too dumb)

- IQ is totally unchangeable and static — nonetheless, you are forbidden from studying or practicing for IQ tests.

So to me, it's not particularly surprising that genetics disappoint in predicting IQ — given that they also fail at predicting other nonsensical and ever-chaning values such as whether I liked today's dinner..