Long odds of an exact repeat mating

24th December 2020

Caption: The brilliant British horse Frankel, regarded by many as the greatest racehorse of all time

By David Brasch

IT is amazing where we find information that pertains to breeding both the racehorse and greyhound.

While recently reading a book on legendaey British racehorse Frankel, the author discussed the fact the mating of champion sire Galileo and the Danehill mare Kind had first produced Frankel, but was repeated a number of times.

This obviously pertains in the greyhound world to why litters of pups are so diverse, and why repeat matings of a champion litter, face almost insurmountable odds to come up with the same success.

Certainly we have seen repeat matings prove highly successful in the greyhound world.

Champion Surf Lorian was the result of a repeat mating and the Just The Best-Barrio Fiesta mating was actually done three times and in each litter there were Group performers.

Hall Of Famer Paua To Burn is another from a repeat mating.

The examples of repeat matings working are far too numerous to mention here.

Frankel, regarded by some (but not me) as the greatest racehorse of all time, was a ‘first-up’ mating.

The author of the book I read gave some astounding figures to show just how difficult it would be for Galileo and Kind to recreate Frankel.

To refresh your memory, Frankel raced 14 times and was unbeaten. He won 10 Group 1’s and his Timeform rating of 147 is the highest EVER!

The author wrote:

However, it does beg the question: were Frankel’s siblings as good as him and if not, why not? After all, if the Galileo-Kind combination has worked once, why not again? It is a commonly held misconception that breeding is that simple. The reason why it is not lies in probability.

Every horse has 32 pairs of chromosomes (canines have 38). When a stallion produces sperm, one chromosome from each of his 32 pairs is randomly introduced into each sperm. So, the chances of another sperm containing precisely the same 32 (38 in dogs) chromosome mix is 2 x 32 (i.e. 2x2x2x2 with x 2 added another 28 times (34 times in dogs) which is to put it mildly a pretty big number of possible combinations.

Exactly the same random chromosome distribution happens in the creation of the egg, so when mating takes place the number of possible combinations doubles to 2 x 64 (or in dogs 2 x 76).

Now this number, despite its mind-boggling hugeness, has a name. It is the chess number, so called because an ancient Emperor, as the legend goes, was so delighted at the creation of the game of chess that he invited the inventor to name his reward. The man asked for rice, the amount determined by the number of grains required to put one grain on the first square of the board, two on the second, four on the third, eight on the fourth and so on with each square having double the number of grains as the square before until the 64th square. The Emperor acceded to this apparently modest request, not withstanding that the total number of grains required is 2 x 64 or 18,446,744,073,709,551,616. No such amount of rice exists in the world. The legend is unclear whether the man was lauded or executed for his cleverness.

It is hard to put this probability in any sort of reasonable context, but let’s try: The chances of getting Frankel’s exact genetic match second time around is roughly the same as every single human being on the planet winning the lottery 54 times each.

Or, that Galileo and Kind would have to produce a foal every year for the next 18 million, million, million years for another Frankel; to come along.

While those figures are daunting to say the least, the reality of it all is that Galileo and Kind were actually mated a total of four times. Frankel was the first, foaled in 2008.

Interestingly, the very next year, 2009, Galileo-Kind produced a colt called Noble Mission. He would win nine races and earn 1.4 million pounds (Frankel earned 3 million pounds).

Noble Mission won two Group 1s, three Group 3s, was placed in seven other Group races including two Group 1s.

He was 2014 champion older horse in Europe and now stands at stud in Japan.

The other two Galileo-Kind matings produced an unraced filly and a failed colt.

I hear all the time, and from legendary greyhound breeders like Paul Wheeler and Richie Dean, never undertake repeat matings. Richie’s great mate, the late Kevin Johns, repeated matings with regular success.

The stats show repeat matings do work.

But, the stats, as shown above, are pretty much against any of us recreating legends like Frankel.