The Sports Gene - Inside the Science of Extraordinary Athletic Performance by David Epstein seems to be an interesting new book.
More so because it features two great Finnish athletes: cross-country ski champion Eero Mäntyranta (whose performance was boosted by a rare gene mutation) and ultrarunner/triathlete Pam Reed (whose father is of Finnish origin). Check out an extract from the book with Pam Reed.
I know there's no such a thing as "the sports gene", but I'll put it on my long 'To Read' list anyway. Meanwhile, it's well worth reading this brief summary of the book.