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The best in the world
WBRR tables shine a light on genetics, Mitochondrial DNA, and the influence of deep female lines, writes Alan Porter
THE TRIO TIED for the top of the World’s Racehorse Rankings – Crystal Ocean, Enable and Waldgeist – pay a tribute to the remarkable matriarch Urban Sea, who threatens to become to the European Classic pedigree what Queen Victoria was to the crowned heads of Europe at the turn of the last century.
Crystal Ocean is by Urban Sea’s son Sea The Stars, Enable, who emerges best if weight-for-sex is taken into account, is by Nathaniel, who is by Urban Sea’s son Galileo, while Waldgeist is by Galileo himself.
Each of the trio in their own way are illustrative of some commercial and genetic talking points of current interest.
One that was picked up immediately when the figures were announced was that Crystal Ocean would retire to stud at The Beeches, one of the NH wings of Coolmore.
It’s long been hard for all but the most stellar middle-distances runners to gain much purchase at stud in Europe, but Crystal Ocean might represent a new extreme.
It’s quite remarkable that one of the year’s leading horses, who gained his most prestigious Group 1 victory over 1m2f, who is by one of Europe’s top stallions, and is a half-brother to two other group/graded winners, one Grade 1, and who is out of a two-year-old stakes winner, isn’t even considered to have a shot as a mainstream Flat sire!
On the other hand every year seems to see a new, almost generic, seemingly interchangable new intake of Green Desert/ Danehill/Acclamation line two-year-old sprinters covering large initial books before gradually fading away, many never to be heard from again as far as high-level performers are concerned.
In passing we have to wonder what kind of opportunities the magnificent Stradivarius – like Crystal Ocean, by Sea The Stars – who topped the extended division again this year, will have to do to make the grade as a Flat sire when he retires.
Last year we noted Enable made some pedigree history as the first Group or Grade 1 winner to be inbred 3x2 or closer to the epoch dominating Sadler’s Wells (although she is not the most closely inbred Prix de l’Arc de Triomphe winner, that title is still held by Coronation V, a dominant heroine of the 1949 running, who was by a son of Tourbillon out of a mare by Tourbillon).
What’s particularly interesting is that the re-affirmation of the closely inbred Enable’s standing as a world-leader came just before publication of a study that raised concerns about the degree of inbreeding in the modern thoroughbred.
Published in mid-January this year, a paper by a team at University College Dublin, led by UCD Professor in Equine Genomics, Emmeline Hill, through DNA analysis of 10,000 thoroughbreds demonstrated that inbreeding across the breed has steadily increased across over the last 45 years.
The concern expressed in the article is that a phenomenon known as “inbreeding depression” can compromise both fertility and health.
The conclusion of the article is that inbreeding has been driven by commercial selection of certain popular sire lines. According to this paper, particularly powerful has been the influence of Northern Dancer (who appeared in the pedigrees of 97 per cent of the horses in the study), his son Sadler’s Wells and his grandson, Danehill. We’d actually speculate that as far as the horses tested here are concerned, the really decisive factor has been Northern Dancer’s grand-dam Almahmoud.
Her daughter Natalma, the dam of Northern Dancer, is 3x3 in the pedigree of Danehill, another daughter Cosmah is dam of Halo, whose son Sunday Silence is the dominant factor in Japanese pedigrees; and another sire Machiavellian is out of a mare bred 3x3 to Almahmoud.
The situation may well be further compounded by the fact that Mr. Prospector, so often a foil for Northern Dancer, is by Raise A Native, a son of Native Dancer and out of Gold Digger, a mare by a grandson of Nearco. Northern Dancer is by a son of Nearco and out of a mare by Native Dancer.
What strikes us as rather counter-intuitive about these statistics is that as a phenotype – the physical horse we see before us – the thoroughbred retains a high degree of hetrozygocity (has lots of genetic variability), and is far more diverse in type than most horse breeds.
That’s probably because, despite it’s name, the thoroughbred really evolved as a category – a running horse – rather than a true-breeding type. The development of the racehorse has been for a complex set of characteristics that make for performance, rather than to create a specific type. This focus on function, keeping those that can run fast (or those closely related to them), and discarding those who don’t, or who are not physically robust enough to run, has kept the thoroughbred remarkably free from inherited disease.
ALTHOUGH THE CAUSE of inbreeding is laid at the door of the focus on predominant sire lines, the paper also observes that there are differences between genomic and pedigree inbreeding in that the degree of inbreeding on the page doesn’t always reflect the degree of genetic homozygosity (possessing two identical forms of a particular gene, one inherited from each parent).
In fact, when we look at Enable – who with Sadler’s Wells 3x2 would be thought of as highly inbred by thoroughbred standards – and take her whole pedigree out to ten generations, we find she has 861 unique ancestors, not a lot less than the average of 884 found among Group/Grade 1 winners in a study of nearly 12,000 thoroughbreds taken from yearlings sold at premier sales around the world in 2015.
Incidentally, the same study showed that Group/Grade 1 winners had a lower average of unique ancestors than any other group in the population.
Professor Hill, warned that the rise in (genomic) inbreeding in the international thoroughbred population could compromise the future of the breed, and counselled that the trend should be combated by using DNA-based tools for choosing genetically diverse mates.
That, however, may prove to be more easily said than done, since it would require either stallion farms making genomic information about their stallions public, or mare owners subjecting their mares to stallion farms for approval on the basis of DNA.
Then there is the question as to whether the “outcross” is synonymous with the “best cross” at least as far as performance is concerned.
Although we have said that the paper noted that inbreeding and genomic inbreeding are not synonymous, there is still a broad link. There is no doubt that if you took a herd of horses with high inbreeding coefficients and another with low inbreeding coefficients, the group with high inbreeding coefficients would also have a higher degree of genomic inbreeding.
With that in mind it’s interesting to note that there appears to be optimal degrees of paper inbreeding, as described by inbreeding coefficient, coefficient of relationship and ancestral history coefficient, all of which indicate that the best runners appear to fall in an optimal range, rather than being the least inbred.
In fact, in the sample previously referred to, Grade 1 winners had a lower ceiling for inbreeding coefficient, but also a higher average and higher floor than any other group separated by ability, similarly their minimum ancestral history coefficient is higher than all other groups.
Enable’s fellow Sadler’s Wells/Galileoline classification topper Waldgeist gives the opportunity to consider another relatively recent genetic development that may have significance to the thoroughbred breed.
Lowe families regaining relevance via mtDNA
At the end of the 19th century the Australian pedigree researcher Bruce Lowe traced back the pedigrees of the winners of the Epsom Derby, the Epsom Oaks and the St. Leger Stakes, then grouped them by direct lines of tail female descent going back to the earliest ancestor found in the General Stud Book.
He then proceeded to arrange these families in order of Classic winners produced, thus the family with the most Classic winners – that whose earliest known descendent was Tregonwell’s Natural Barb Mare – became family No. 1, the Burton Barb Mare and her descendents was family No. 2, and so on.
Lowe ended up with 43 families, a number that has since been expanded, and now includes American, Colonial, and some halfbred families.
This concept of designating numbers to the various Thoroughbred female families was popularised when Lowe’s work Breeding Horses by the Figure System was published posthumously in 1895 by his friend and editor, William Allison.
In addition to the historical research, Lowe added some rather fanciful theories about how to utilise the family numbers in a breeding programme.
Lowe’s ideas suffered a body blow in the late 1930s when Phil Bull, founder of Timeform, conducted an analysis of what he called the “430 worst horses in training” and revealed that the representation of the Lowe families among the worst was proportional to their representation, the No. 1 family the highest number, the No. 2 family was the second highest.
This effectively ended the use of family numbers in planning breedings, but many still use those notations as a convenient way to categorise thoroughbred families.
Having said that, and acknowledging that Lowe’s theories are never likely to return to vogue, his work may have more relevance to breeding than might have been thought. This is because of Mitochondrial DNA (mtDNA), which exists outside the nucleus of the cell, and is passed on exclusively through the female line.
Mitochondria have numerous vital functions, one of which is energy production, hence the description “the power pack of the cell,” and it plays a vital role in aerobic component of athletic performance.
The average overall rate of mutations in mtDNA are measured in thousands of years, which means, if we take for example, Enable, who is from Bruce Lowe family 4 (sub-branch m) she will have the same mtDNa as the earliest-known direct female ancestress, The Layton Barb mare, who was at stud in the second half of the 17th century.
This has become much more important with the relatively recent discovery that there are important interactions between mtDNA and nuclear DNA – or in pedigree terms the female line and the rest of the pedigree. As a result there is the potential for a stallion to combine particularly well with mares from a particular female family (mtDNA line), even though those mares may only be connected by a distant ancestor.
Just after the turn of the most recent century scientists began to investigate the equine mtDNA genome, and subsequently established haplogroups (a genetic population group who share a common ancestor) and haplotypes (a group of genes within an organism that was inherited together from a single parent).
Subsequently researchers have harmonised the Lowe family numbers with the Achilli mtDNA haplotypes, in the course of which discovering several instances where the haplotype differs from what is suggested by the stud-book record, the majority of which are very distant both in time and generations from the current population.
The Bruce Lowe No 5 family
One of the most interesting of these anomalies impacts the Bruce Lowe No. 5 family. The majority of this family are Achilli haplotype B1a, but the 5g and 5h are D1b. This is a deep-rooted error which appears to stem from the 5g/5h foundation mare Miss West (born in 1777) being wrongly attached to root of the No. 5 family in the 5th edition of the General Stud-Book.
Rare globally and stemming from the same root as the Shetland Pony, Icelandic Pony and Norwegian Fjoird, in the thoroughbred it is only found through the 5g/5h family. Looking at the pedigrees of early thoroughbreds, it’s rare that we find more than one individual from the 5g/5h in any single pedigree, which would have considerably reduced the likelihood of the optimal nuclear/mtDNA combination for individuals from this female line to occur.
This state of affairs began to change from the early 1930s. “When Blandford met D1b” isn’t quite as catchy as “When Harry met Sally,” but it proved to be both a lot less rocky romance, and a breed-shaping combination.
The number of foals by Blandford – a three-time champion sire in England – out of mares from the D1b mtDNA line could be counted on the fingers of a hand with a couple to spare, but they included the Prix de la Salamandre and Prix du Conseil General winner Blue Skies, and a Yorkshire Oakswinning filly to whom we will return in a moment.
Blandford line saved by D1b and extended by Sadler’s Wells The Blandford sire line, however, would have disappeared quite quickly had it not been for the D1b haplotype.
The 1930 Epsom Derby winner Blenheim, Blandford’s best stallion son, was out of a mare by the foul-tempered but talented Charles O’Malley, a member of the D1b tribe. The branch of Blandford descending from the great French runner Brantome saw it’s last outstanding stallion in Val De Loir – champion sire in France in 1973, 1974 and 1975 – emerge from the D1b family, his fourth dam Simons Shoes being a three-quarters sister to Charles O’Malley.
Blandford’s fine son Windsor Lad, whose victories included the Epsom Derby, the St. Leger, the Eclipse Stakes and the Coronation Cup, had a short-lived sire line that extended furthest via son Windsor Slipper, an undefeated winner of the Irish Triple Crown. He, too, was from D1b mtDNA haplotype – his dam Carpet Slipper being out of Simons Shoes.
Best of all Blandford’s offspring as a runner was the undefeated English Triple Crown winner, Bahram.
Only moderately successful as a stallion in a career that saw him stand in England, the US and Argentina, Bahram is the conduit through which a branch of the Blandford sire line is still represented.
Bahram’s son Persian Gulf wasn’t from the D1b mtDNA line, but his grandsire Willbrook was – being also out of a mare inbred 3x2 to Lord Gough (also in the pedigree of Blandford), a son of the magnificent “Avenger of Waterloo” Gladiateur, a horse who was from the D1b tribe.
The Persian Gulf line comes down to the present day through Tamerlane and Dschingis Khan to German Horse of the Year Kongisstuhl, and thence to that horse’s son, Monsun.
Konigisstuhl was from the D1b maternal line and carried the previously mentioned Blandford/Db1 horse Blue Skies. Monsun was also inbred 4x4 to Kongisstuhl’s third dam Kaiserkrone and her brother, Kaiseradler.
Considering that the Db1 haplotype represents only two per cent of the breed, and less than that until relatively recently, it’s remarkable that four male lines of Blandford extended through horses from that branch. We also mentioned that there was a notable mare by Blandford from that maternal line.
So what of she? That mare was Dalmary, who showed herself to be among the best of her sire’s daughters with a win in the Yorkshire Oaks. Dalmary was out of Simons Shoes, so had a very similar background to Blenheim – both by Blandford, with Blenheim being out of a mare by Simons Shoes’ three-quarters brother, Charles O’Malley.
The results of that union included Moccasin, who earned a US Horse of the Year title as a two-year-old filly, a champion two-year-old colt in Ridan, stakes winner Lt. Stevens, who is broodmare sire of Lear Fan and Alysheba, and Thong, who produced four major stakes winners, and who is grand-dam of Nureyev and third dam of Sadler’s Wells and Fairy King.
Circling back to Waldgeist – he is by Galileo, a son of Sadler’s Wells (D1b), out of a mare by Monsun, a son of Konigsstuhl (D1b), and is himself from the D1b maternal haplotype. Bearing in mind that, until Rough Shod and her descendants, it was rare in the extreme to see more that one member of the D1b family in a five-cross pedigree, this is very striking.
Galileo apart, Sadler’s Wells has, of course, founded male-lines that have reached throughout the world, and on occasion found some surprising manifestations, one of those being Code Of Honor, 2019’s top-rated Dirt three-year-old.
A member of the first crop of Frankel’s brother Noble Mission, Code Of Honor won the Travers Stakes (G1) against his fellow three-year-olds, and the Jockey Club Gold Cup (G1) over his elders.
On a mark of 122, Code Of Honor was actually rated superior to any of Frankel’s offspring in 2019, although Frankel did have seven horses in the WBRR, including Logician, whose victory in the St. Leger (G1) saw him as the top threeyear-old over the extended distances. Interestingly enough, Frankel also supplied two of the nine horses from four and up to be rated at extended distance.
Whether or not it’s just a reflection of the mares to which he has been bred, it seems that, by and large, Frankel is clearly getting more stamina than speed, which is interesting for a horse who impressed – at least on 2,000 Guineas (G1) day – as being quick enough to win an event like the July Cup (G1)!
Australia’s top three-year-old Castelvecchio is another scion of the Sadler’s Wells line. He’s by Dundeel, a son of High Chaparral, and out of a mare by Zabeel, whose own broodmare sire is Nureyev.
This means that he has the three-quarters brothers from the D1b family mtDNA haplotype 3x5.
That combination reversed – a Nureyev-line stallion with Sadler’s Wells in the dam – produced the top-rated three-year-old Sottsass, successful in the Prix de JockeyClub (G1) and third to his elders in the Prix de l’Arc de Triomphe (G1).
He is by Siyouni (by Pivotal, by Polar Falcon, by Nureyev), out of a mare by Galileo. Siyouni is firmly placed as one of the stars of the European stallion firmament, but Farhh, a lower profile son of Pivotal, supplied the Queen Elizabeth II Stakes (G1) victor King Of Change.
He is rated just three points below Sottsass in the three-year-olds rankings. Farhh is also sire of Dee Ex Bee, jointsecond to Stradivarius among the older extended distance runners.
King Of Change is out of a mare by Echo Of Light, whose dam is by Sadler’s Wells, so he has Nureyev/Sadler’s Wells 4x4.
Dee Ex Bee is bred on a similar cross to King Of Change – his dam is a sister to Dubai Millennium, the sire of Echo Of Light.
Not to be outdone, Fairy King, the brother to Sadler’s Wells, and three-quarters brother to Nureyev, is in the sire line of Beauty Generation, the Hong Kong-trained star who took top spot among older horses at the middle-distance.
He’s by the New Zealand sire Road To Rock, who’s by Fairy King’s leading stallion son, Encosta De Lago.
That line has another representative on the classification in Australian-bred Yes Yes Yes, who won the world’s richest Turf event, The Everest, and is the joint-second rated three-year-old sprinter.
He is from the first crop of Rubick, a son of Encosta De Lago and out of a three-quarters sister to Redoute’s Choice (Danehill).
Encosta De Lago and Redoute’s Choice also combine in another promising young sire, the reverse shuttler Zoustar.
Out of a Redoute’s Choice mare, he is by the short-lived sprint star Northern Meteor, who was by Encosta De Lago out of a granddaughter of Moccasin, having the sisters Thong and Moccasin 5x3.
Storm Cat succeeding around the world Another branch of the Northern Dancer line that is beginning to show both considerable internationalism, and aptitudinal diversity, is that of Storm Cat.
Horses from the Storm Cat line would have dominated the sprint division, had it not been for Battaash, who is by Dark Angel, from the Acclamation/Royal Applause line.
Joint-second in the rankings of older sprint runners were Blue Point (by Shamardal, who is by Giant’s Causeway, a son of Storm Cat) and the Australian Santa Ana Lane (by Shamardal’s rapidly-rising son, Lope De Vega).
The highest-rated three-year-old sprinter was Ten Sovereigns, who is from the first crop of No Nay Never, a very fast son of Scat Daddy, who goes back to Storm Cat via Johannesburg and Hennessy.
Scat Daddy died at the tragically early age of 11, but in the US he has the Triple Crown winner Justify and Into Mischief’s Grade 1-winning half-brother Mendelssohn, both with first foals in 2020. In Europe, No Nay Never flies his flag and in addition to his record with precocious runners and sprinters, he also has a Chilean Oaks (G1) winner from a southern-hemisphere crop.
Other Group 1-winning Scat Daddy sons Caravaggio and Sioux Nation, and the newly-retired Ten Sovereigns in Europe, mean that the chances of his male-line thriving over the next decade or two look bright.
To complete the Storm Cat sprinting story, we should also add that the top-rated Dirt sprint filly (and co-highweighted sprint female) Covfefe is by Into Mischief (Harlan’s Holiday), a great-grandson of Storm Cat.
Having appeared as grand-sire of the top US sprinter Mitole, Giant’s Causeway himself was represented by a totally different type of horse in Bricks And Mortar, a champion Turf Horse and Horse of the Year in the US for 2019, winner of the Breeders’ Cup Turf (G1) and rated 122. He begins his stud career at Shadai Farm, Japan, in 2020.
The Mr. Prospector line, so long the outstanding foil for Northern Dancer, is also undergoing some interesting international diversification.
Seeking The Gold, one of Mr. Prospector’s best sons, was unable to found a major sire line in the US, but through the one crop of his brilliant son Dubai Millennium is responsible for Dubawi.
He had no less than 11 horses on the ratings. His son Night Of Thunder made a tremendous start with his first two-year-olds in 2019, which has also served to further heighten enthusiasm for newly-retired Dubawi son Too Darn Hot.
He was the top-weighted European juvenile of 2018, and top-rated Turf miler among the three-year-olds in 2019.
Santa Ana Lane
Alizee, by Sepoy (Elusive Quality), tied with Covfefe as leading filly or mare
Joao Moreira on board Glory Vase
The career of the remarkable Australian mare Winx, joint top-rated in 2018, ended in April 2019. By then she was a seven-year-old by southern-hemisphere time, and eight by northern hemisphere standards. In the space of eight weeks last southern hemisphere season, she won all four of her starts with the last being her 33rd straight victory.
Although she was rated below two other females – Enable and Lys Gracieux – on the overall classification, she was still the top female at a mile.
Winx is a daughter of Street Cry, who was by Mr. Prospector’s European-raced son Machiavellian, out of the Irish Oaks (G1) heroine Helen Street, who did not race on Dirt. Street Cry’s North American-based son Street Sense came close to getting a divisional leader with Mckinzie being second top-rated Dirt miler, while another son, the Breeders’ Cup Juvenile (G1) scorer New Year’s Day and now standing in Japan, is sire of leading three-year Dirt horse, Maximum Security.
He lost the battle, being disqualified after winning the Kentucky Derby (G1), but won the war taking the three-year-old colt Eclipse Award.
Another Elusive Quality son Sepoy was represented by the Australian filly Alizee, who was tied with Covfefe for overall leadership of the filly and mare division.
Kingmambo hitting heights in Japan
The Fappiano branch of the Mr. Prospector line has brought us such talented horses as American Pharoah, who headed the World Racehorse Rankings in 2015, Arrogate, who was top-rated in both 2016 and 2017, and Gun Runner.
He was less prominent in the upper reaches in 2019, but did supply Midnight Bisou (a son of Midnight Lute from the Fappiano line) the top-rated Dirt mare of 2019.
Another branch that has made less of an international impact outside of America is that of Smart Strike, who provided the highest-rated US horse of 2019 in Vino Rosso, who was just two points off the top-rated horses of 2019.
Winner of the Breeders’ Cup Classic (G1) on his last appearance before retiring to stud, Vino Rosso is by Curlin, a Smart Strike son who twice earned honours as Horse of the Year. He is now firmly ensconced in the upper echelons of the Kentucky stallion colony.
We mentioned that the Seeking The Gold branch of Mr. Prospector has needed to go outside of North America to establish a thriving male-line, and the same can be said of Kingmambo.
His best stallion son has probably been the Japan Derby (G1) winner King Kamehameha. He died last year, but left behind Lord Kanaloa, himself a leading sprinter – and a horse who looks a worthy heir to his sire.
With just two crops of three-year-olds and over he was represented by Almond Eye – whose victories in last year’s Dubai Turf (G1) and Autumn Tenno Sho (G1) saw her become the leading older mare in the intermediate category – and the champion Japanese three-year-old colt Saturnalia, just three points off top of the three-year-old classification.
Rulership, another son of King Kamehameha, had two runners, Kiseki and Mer De Glace, in the long distance category. In 2019, Japanese breeding suffered a double blow, as less than two weeks earlier, the country’s 12-time leading sire Deep Impact, who stood alongside King Kamehameha at Shadai Farm, died.
Deep Impact had 11 individuals in the WBRR’s, including Glory Vase, who was only two points off the top-rated trio.
The sire’s influence has a chance to become internationally significant as he has the Classic winner Saxon Warrior in his second season at Coolmore in Ireland and shuttling to Australia, where at least three other Grade 1-winning sons of Deep Impact hold court.
His Prix du Jockey-Club (G1) winner Study Of Man (rated 115 this year) is now at Lanwades Stud in Newmarket. However, the actual highest-weighted Japanese horse of 2019 was not by Deep Impact, but by a fellow son of Sunday Silence, Heart’s Cry.
This is Lys Gracieux, who closed her career taking the Takarazuka Kinen (G1), the Cox Plate (G1), and the Arima Kinen (G1) . Heart’s Cry is also gaining a high-level international representative at stud in 2020 in Yoshida, a Grade 1 winner on Dirt and Turf in 2018, who appeared at 119 on this year’s classifications.
Out of the US Grade 1-winning sprinter, Hilda’s Passion, he kicks off his stud career at Winstar Farm, Kentucky.
