A Troublesome Inheritance: Genes, Race and Human HistoryWatch
It seems to follow in the footsteps of economist Greg Clark's "A Farewell to Alms" and "The 10,000 Year Explosion: How Civilization Accelerated Human Evolution". Books that might fall into a category described as "bio-history".
It takes thousands of years for genes to mutate and evolve not 600 years. He is obviously chatting bull****. The "genetic characteristics of the English Lower class" indeed! I wouldn't waste a penny of my working class money on his book.
That said, I don't think Wade is saying that the genetic changes were restricted to the last 600 years, he's saying that genes are a factor in pre-adapting those populations for the development /progress that has been observed.
For instance, factors like adapting to winter climates, greater demand for paternal investment, the rise of State societies and rule of law, create evolutionary pressures; among them were selection for qualities that were beneficial in our larger communities, such as lower levels of aggression, deferred gratification (vital for farmers), a greater willingness to trust people outside of close kin group, and the qualities required for craftsmanship, finance and various other complex skills...
The same could be said for China and East Asia, which I understand Wade also touches on.