Literature

It has long been recognised by the horseracing community that loving care and a good jockey are important factors in winning prizes. However, such is the hunger for success that breeders seek out every possible advantage for their next generation of hopefuls. The lure of 'good genes' has proved remarkably strong, turning stud farms into multi-million pound (dollar) industries. By combining the genes of a successful mare with those of a winning stallion, the progeny should be well-equipped genetically to compete. The racing industry effectively runs an equidian eugenics programme to improve the genetic qualities of competing animals.
Unfortunately for the participants, genes are not all they are made out to be. We have been exposed to the 'Genes-R-Us' emphasis for so long that it is very hard for people to correct their thinking. Nevertheless, major corrections are warranted, according to Wilson and Rambaut, who have just published their study of over 4000 racehorses. "Only 10 per cent of a horse's winnings can be attributed to parentage. [snip] The majority - up to 90 per cent - of a horse's lifetime winnings rest on how the horse is reared, trained and ridden and not to its genetic inheritance." Nurture, rather than nature, provides the primary factors affecting success. Furthermore, the authors could find no correlation between stud fees and the horse's lifetime earnings.
The surprise expressed at the research findings is an indication of just how entrenched the genocentric view of life has become. Why do we put so much emphasis on genes? The simple answer is that this derives from the origins story we have been fed for most of the 20th Century: the organism is just the vehicle for genes to reproduce themselves.
Research findings that contradict this dogma have been accumulating steadily and we are now overdue for a change. For more on this, go here. Unfortunately for Darwinists, the nurture factors do not change the genome: if nurture effects become significant, they undermine the efficacy of Darwin's mechanism of variation and natural selection. In a Nature news report, Kaplan cites the figures 91.5 percent nurture and 8.5 percent nature. He also cites Wilson saying:

"8.5% may seem small, but for those of us studying the benefits generated by genetics in wild animals this is huge [. . .] In the wild, where environmental conditions vary a lot and survival can depend on luck as much as anything else, genetics usually account for about 1-2% of survival rates."

These figures ought to be more widely discussed in the context of natural selection. Do models of natural selection do justice to the revelation that genetics usually account for about 1-2% of survival rates? Should students be taught about these figures, or are they deemed unable to handle them judiciously?

Breeding racehorses: what price good genes?
Alastair J. Wilson, Andrew Rambaut
Biology Letters, FirstCite, Dec 18 2007, doi 10.1098/rsbl.2007.0588

Abstract: Horse racing is a multi-million pound industry, in which genetic information is increasingly used to optimize breeding programmes. To maximize the probability of producing a successful offspring, the owner of a mare should mate her with a high-quality stallion. However, stallions with big reputations command higher stud fees and paying these is only a sensible strategy if, (i) there is a genetic variation for success on the racecourse and (ii) stud fees are an honest signal of a stallion's genetic quality. Using data on thoroughbred racehorses, and lifetime earnings from prize money (LE) as a measure of success, we performed quantitative genetic analyses within an animal model framework to test these two conditions. Although LE is heritable (VA=0.299 +- 0.108, Pr=0.002), there is no genetic variance for stud fee and the genetic correlation between traits is therefore zero. This result is supported by an absence of any relationship between stud fees for currently active stallions and the predicted LE for their (hypothetical) offspring. Thus, while there are good genes to be bought, a stallion's fees are not an honest signal of his genetic quality and are a poor predictor of a foal's prize winning potential.

See also:

Highfield, R. High price may not make champion horse, The Daily Telegraph: 19/12/2007.

Kaplan, M. Good genes help racehorses to be winners, news@nature.com, 18 December 2007 | doi:10.1038/news.2007.387