Grey Power

What is it about the grey? Long have they held a special place in the hearts of racegoers, with an allure that has morphed into theory and legend. 

Names such as Subzero, Efficient, Schilliaci, Deck The Halls and, of course, the mighty Gunsynd immediately conjure a sense of something special and give rise to debates about the bravery of the grey, their ability to handle wet tracks, and their toughness as competitors. 

But is there any truth to these myths? Are these famous greys genetically superior to other horses, or is their colour insignificant when it comes to performance? 

There are plenty of theories related to the ability and personality of grey thoroughbred, but most are coincidental. 

For example, there are far fewer greys than bays or browns born each year and that means fewer get to the racetrack. Because of this, it seems that all greys have ability. They stand out more on a racetrack when they win, but there are plenty of slow ones, too.

All grey thoroughbreds around the world are thought to be descendants of an Arabian stallion named Alcock’s Arabian. Widely accepted as the very first grey horse, Alcock’s Arabian was foaled in 1700 and imported to England in 1740 from Constantinople. His owners named him The Brownlow Turk and this caused some confusion for many years, as records didn’t indicate the name change. 

Today, about three per cent of the thoroughbred population is grey and research undertaken at Uppsala University in Sweden in 2008 has shown that a genetic mutation of the pigment cells actually causes the grey colouring. The research found mutated genes in more than eight hundred grey horses from eight different breeds. Crucially, the variants are not present in horses of other hues.

A grey horse is born coloured (black, brown or chestnut).The full extent of the grey colouring in thoroughbred horses is often not seen until the horse is one or two years old, with some horses nearing a white shade by age five or six. This means that it is often difficult to record the colourings of foals and weanlings because the grey can be mottled with other more dominant colours. That same horse might be near white a year later, but they take on a grey appearance due to their black skin underneath. The process resembles greying in humans, but the process is faster in these horses.

While greys are still a small fraction of the horse population, their numbers have increased in the past 30 plus years due to the breeding success of certain grey thoroughbreds. The most influential horse (through his grey descendants) in this regard was the New Zealand-based, but Irish-bred, grey stallion Sovereign Edition from the 1970s.  

Such is the fascination with the grey that they even have their own special ‘greys-only’ race during her Melbourne Cup Carnival: the Off The Track Subzero Handicap (1400m) on Kennedy Oaks Day. 

The all-greys race was introduced to the Oaks Day schedule in 1996, when an expansion of the Melbourne Cup Carnival racing program occurred. It was intended to provide something different in racing entertainment, and has been successful in this regard since the beginning. 

Certain grey horses are also given the opportunity to play an important role on race days since their racing careers are over, thanks to a tradition involving the Clerk of the Course. Historically, the Clerk of the Course’s horse has been grey, a tradition that can be traced back to England and the beginning of racing. Grey horses were selected as they were the minority colour so stood out from horses competing in races on the day.


Some Iconic Greys


Known as ‘The Grey Flash’ and one of the world’s best sprinters, Chautauqua retired from racing in 2019 and is now embarking on a career as a show horse. 


One of the most-loved greys in Australian racing, Subbie took out the 1992 Melbourne Cup, then post-retirement continued to please crowds with his role as Clerk of the Course horse and various ambassadorial appearances. Heading for his 32nd birthday in 2020, the recipient of thousands of pats from children is still making people smile.


The ‘Goondiwindi Grey’ was the pride of Queensland with a string of wins in the early 197os. He was known as a fierce fighter on the track, but a big softie off it, with stories of the grey resting his head on people’s shoulders and standing perfectly still while children crawled all over him. 

Melbourne Cup winners that have been grey

There have been six individual grey horses to win the Melbourne Cup. They are: Toryboy (1865); Hiraji (1947); Baghdad Note (1970); Silver Knight (1971); Subzero (1992) and Efficient (2007).


“In the grey horse, the hair begins to lose its pigment at an early age, either partially or totally. The colour of the hair is the result of a reaction which takes place when the melanic pigment of the skin undergoes a chemical transformation on penetrating into the hair.

“When this reaction, and with it the possibility of transmitting colour to the hair, no longer takes place, the hair itself turns grey. It seems the penetration of air between the inner and outer substance of the hairs accentuates the loss of colour.” 

Source: Federico Tesio’s book on ‘Breeding the Racehorse’ (Tesio, ‘Breeding the Racehorse’ page 28, 1958)