Where's the Point Of Too Much?

Author: Jane Nemecek, published: 16th July 2023; updated: 12th Feb 2025

The 2023 spring was uneasy for racing fans. The attention was focused on Churchill Downs, injuries, and drug tests, and there's still noticeable vigilance among fans on social media. Many of us feel that some affairs were handled in quite an unfortunate way.

A series of pre-Derby injuries also intensified discussions about the "genetic unsoundness" and its possible causes: inbreeding or particular bloodlines. It's not my intention to discuss these issues in depth today: I respect the possibility of inherited predispositions and appreciate that authorities support genetic research in this field, with some studies already published. However, I think we're still too far from any conclusions, links to both "suspects" included. And I'm also worried that whatever theses, markers, or possibly even tests we can come up with, it's still only training that can determine a horse's ability to withstand it.

Speaking about inbreeding from an analyst's perspective, little can happen between the third and fifth generation of pedigrees, and names like Nashua are far more surprising than inbreeding techniques themselves. Statistically, European and American data on inbreeding & its various aspects are almost a spot-on match: Considering how strongly the topic resonates due to American fatalities, it adds some food for thought.

As a pedigree analyst, I have more serious concerns than inbreeding. Tendencies in current European pedigrees & breeding are worrying, and they are both apparent when examining pedigrees and verifiable statistically. Most of all: they seem to have a practical impact on the breed.

After a lengthy consideration due to the seriousness of possible conclusions, I decided to summarize these trends & explain my concerns. I miss them as topics in public debates, including those where American breeding is a designated "problematic child." Whatever your opinion on the matter is, know that none of the issues discussed in this article afflicts American pedigrees.

1. Cumulation of sirelines

For the sake of correctness, as well as due to the fact that I don't want to harm any horse, breeder, or affect decisions, I made the following paragraphs "name free," although it may look a bit quixotic.

Let's take a pedigree of one particular colt, the Gr.1 winner of the 2022 season. He's not a product of any hot nick, being out of a Born to Sea mare, and he's modestly inbred - 4x5x5 to Mr. Prospector and 5x5 to Danzig. But when you take a closer look at his bloodlines, he's by No Nay Never (Storm Cat - Northern Dancer), out of a Born to Sea mare (Green Desert - Northern Dancer), out of a Pivotal mare (Nureyev - Northern Dancer), out of an Anabaa mare (Danzig - Northern Dancer). It means four lineages of Northern Dancer among the first four sires.

Many European breeders somehow realized that not just it's a good idea to create nicks within Northern Dancer - it's best to cumulate him. In 2022, we had 8% of successful European Group horses with similar pedigrees - with four consequent lineages of Northern Dancer stallions. Moreover, 34% of Group runners had a triple incidence of Northern Dancer among the first five sirelines, and 12% came from linebreeding. And for the record, yes: there are also attempts to use Northern Dancers in all five consequent sirelines.

In other words, we are currently trying to build the entire pedigrees with ONE sireline.

Two problems are coming our way at this point. First, what will happen when our No Nay Never stallion meets mares with similar pedigrees? And this is pure reality, with - as you can count up - more than 50% of current runners carrying linebreeding or a more intensive combination.

Let's take another look at the hypothetical pedigree above, of our stallion's mating to such a mare. She has only three subsequent lineages of Northern Dancer in her pedigree but both her sire and dam are linebred. The dark blue background in the pedigree table marks Northern Dancer stallions, and the picture is truly worth a thousand words.

Each time I see a pedigree like the one of our hypothetical mare, I want to ask breeders - How far can we take this? Where should we stop cumulating Northern Dancer?

Where do we even head with animals like this hypothetical foal...?

I want all of us to be realistic about the situation: most stallions are NOT bred like the sample stallion yet. On the other hand, the model pedigree consists of two real horses, runners of the 2022 season. And you see its components: Frankel is linebred; both young second dams are linebred. So is, for example, Dansili, Oasis Dream, or Exceed And Excel. And even when mated to mares from different sirelines, these stallions already produce inbred young sires in current rosters. The mathematics is merciless here: two linebred horses will always have a foal with four incidences of Northern Dancer. And the foal will always pass them on.

There's an essential detail behind all of this. European statistics of breeding strategies reveal that this is an intentional strategy of European breeders. How can we tell? The answer is simple: the cumulation of sirelines is not a preferred technique. Its global prevalence for all other sirelines is about 0.1-2% of local populations, whether we talk about linebreeding or more intensive strategies. Only American linebreeding to Mr. Prospector stands out as locally specific but still has a 6% incidence, with one attempt to add the third cross. American incidence of linebreeding to Northern Dancer is only 2.3%; three subsequent lineages have 1.1%, and four 0.1%. The same European numbers for Northern Dancer are 12.1%, 13.2%, and 4.5% of the local population, corresponding with about 180 top Group runners in a single season. This is far beyond coincidence or random tries.

There's also a second problem, which I want you to consider right now. How long will it take to "cover" these horses with non-related partners in the future pedigrees? A sober guess is - at least 2-3 generations, which means we are talking about decades already.

However, this is where our problems only start, as some other issues are tightly interconnected:

2. Inbreeding

Let's start with an opening statement: It's impossible to have a young sireline four times in a pedigree without having a corresponding inbreeding.

However, Northern Dancer has been around for 60 years and had tens of influential sons at stud, not just Sadler's Wells, Danzig, Storm Bird, and Nureyev. Inbreeding to him now doesn't stop at four or five incidences: it goes as far as the 9th generation and up to incredible 12 incidences of Northern Dancer in a pedigree.

This time, I don't want you to imagine a resulting pedigree from the mating of such horses. But while these numbers are rare, 7-9 incidences per pedigree are not, with about 16% of Group horses. Blackbeard himself carries, except for the stallions marked in his pedigree above, five more incidences of Northern Dancer via dams of Johannesburg, Scat Daddy, No Nay Never, and his own. Average inbreeding to Northern Dancer for European group pedigrees is now five times per pedigree.

A bigger part of Northern Dancer's incidence is hidden behind the fifth generation of pedigrees already, which only makes us unaware of the extent of the situation. But how can we think this has no effect? It seems absurd to me to be scared of a 4x5 inbreeding to Mr. Prospector and, at the same time, ignore a 5x6x6x6x6x6x7x7x7 inbreeding, thinking it doesn't project into a horse's genome.

3. Scale of available bloodlines

As a European breeder, you may find yourself in this situation: you have an inbred top mare, like Alpinista, and want to breed her to a stallion with different bloodlines. Where do you find them?

In case you didn't notice by reading the results, 78% of current European top Group runners are Northern Dancers, perfectly mirroring the distribution of powers among sires. You can mate to some proven Mr. Prospector - this is a valid point. But if you try to look at anything outside these two sirelines, you may be badly surprised:

Nasrullahs disappear rapidly as Le Havre died in March 2022, and Sir Percy was retired from stud duty in September 2023. For Grey Sovereigns, Kendargent was 21 this season but Goken remains a sound option. Domestic Turn-Tos were completely replaced by Sunday Silences already. And Blandfords (Monsuns) are considered national hunt stallions, despite a number of flat Gr.1 progeny.

Even worse news is, all these stallions, even when proven Group sires, score "average" at best, or place somewhere near the bottom ranks when compared to Northern Dancers and Mr. Prospectors.

You still have several more options outside the rankings of my 2022 analysis. Man o'Wars - Dream Ahead and his son Al Wukair - didn't have a lucky season and are missing in the statistics. You can also reach for German stallions, including Nasrullah's blood - Lord of England died in 2021, but his son Isfahan is only 11. And finally, you can look for minor sires like Pearl Secret, a French Djebel. However, this is already a point where you may be severly compromising your chances for success.

4. Lack of alternatives

At this point, you may realize that your European options may be limited. I hear you say - we could still breed abroad.

Well, Australia is currently busy using European and American shuttle stallions with local Danehills. Japan's Sunday Silence is another legitimate option, but Europe doesn't seem too fond of them - and a single sireline is not a long-term solution, anyway. The same would be true of Australian Zabeels, a truly great local blood originating in the Epsom hero Sir Ivor. And the American stallions remain another sound option - but mind you, their bloodlines are based on the same Northern Dancer and Mr. Prospector, only to a smaller extent.

Other bloodlines sound too "dirt" and certainly non-typical for European pedigrees: A.P. Indy, American Grey Sovereigns like Uncle Mo and Nyquist, or minor lineages like Man o'War - Tiznow, or Plaudit - Mucho Macho Man. I'm sure the idea of Plaudits at Epsom can evoke a whole palette of emotions, but these bloodlines would still guarantee top quality. We have some even rarer sirelines around the planet - great old ones like Teddy, St. Simon, Ribot, Hyperion, and Djebel. Commando is still possible to find, too. But accessibility aside, few of these sires are proven stakes producers, so this would be a very painful solution.

The previous text suggests one unpleasant truth: the global breeding is effectively stuck with a handful of bloodlines: Northern Dancers, Mr. Prospectors, Nasrullahs + Grey Sovereigns, and Turn-Tos. All other sirelines - and there are not a few of them, you can notice even from the brief listings in this text! - are, more or less, fighting for survival.

5. Related bloodlines

One of the previous sentences closes a particular circle of thoughts. People often mention the impression of the decreasing number of sirelines, and I just added the idea of a few living sirelines. Now, the headline uses the term "related." Let's sort things out:

First, it's not so easy with sirelines because they constantly keep developing. They lack any universal definition - it's only possible to "define" them for some particular purpose and from a specific perspective. In the 1970s, articles described Florizel, Persimmon, and Rabelais as sirelines - but two of them vanished since then, and their overall shares in pedigrees are negligible. Nowadays, it would be impractical to insist on the old taxonomy, and I use St. Simon instead to cover all three lineages. Another good example is Northern Dancer: we now have his numerous sons, but within several decades, the most prolific ones will be distinguished as new sirelines.

For this reason, it's impossible to treat sirelines as any definite group - all the more so as a group that only loses its members.

The second half of the 20th century saw the extinction of several sirelines, like Hurry On or Orby, and therefore a reduction of its count, that's true. But while many discussions end at this point, I consider one aspect far more important: all remaining dominant sirelines are Phalaris - which means they are closely related.

To demonstrate the situation, I'll use a scheme of sirelines - some European lineages of the Darley Arabian clan. Still, you can see how former nicks used to look like: how genetically distant were combinations like Blandford x Nearco or Teddy x Hyperion. Former super-successful nick Nearco x St. Simon is not even in the scheme - whether you stick to the "old" King Fergus origin or the "new one," Byerley Turk's. It also means that "traditional" Byerley Turks - Tourbillons and Djebels - are not shown; neither are Godolphin Barbs, such as Hurry On or modern European Man o'Wars.

Scheme 1: Darley Arabian's sireline, Eclipse - Whalebone European branches

• Whalebone (GB), 1807
  • Camel (GB), 1822
    • Touchstone (GB), 1831
      • Newminster (GB), 1848
        • Lord Clifden (GB), 1860
          • Hampton (GB), 1872
            • Bay Ronald (GB), 1893
              • Dark Ronald (IRE), 1905
                • Son-In-Law (GB), 1911
              • Bayardo (GB), 1906
                • Gainsborough (GB), 1915
                  • Hyperion (GB), 1930
  • Sir Hercules (GB), 1826
    • Birdcatcher (IRE), 1833
      • Oxford (GB), 1857
        • Sterling (GB), 1868
          • Isonomy (GB), 1875
            • Isinglass (GB), 1890
              • John O'Gaunt (GB), 1901
                • Swynford (GB), 1907
                  • Blandford (IRE), 1919
      • The Baron (IRE), 1842
        • Stockwell (GB), 1849
          • Doncaster (GB), 1870
            • Bend Or (GB), 1877
              • Ormonde (GB), 1883
                • Orme (GB), 1889
                  • Flying Fox (GB), 1896
                    • Ajax (FR), 1901
                      • Teddy (FR), 1913
                • Orby (IRE), 1904
              • Bona Vista (GB), 1889
                • Cyllene (GB), 1895
                  • Polymelus (GB), 1902
                    • Phalaris (GB), 1913
                      • Pharos (GB), 1920
                        • Nearco (ITY), 1935
                          • Nasrullah (GB), 1940
                          • Royal Charger (GB), 1942
                            • Turn-To (IRE), 1951
                          • Nearctic (CAN), 1954
                            • Northern Dancer (CAN), 1961
                      • Sickle (GB), 1924
                        • Unbreakable (USA), 1935
                          • Polynesian (USA), 1942
                            • Native Dancer (USA), 1950
                              • Raise a Native (USA), 1961
                                • Mr. Prospector (USA), 1970

With nicks like Blandford x Nearco and Teddy x Hyperion, you don't get closer than 10 different generations of ancestors. And Whalebone was the 8th-generation descendant of Darley Arabian, which means that with the other two clans and their sirelines, you get even significantly further, to about 20 generations of genetically non-related ancestors.

That's how things used to be. Nowadays, we have neverending combinations between Nasrullah, Northern Dancer, and Turn-To: all born within two generations from Nearco. Mr. Prospector takes it a bit further to Phalaris but still not more than six different generations.

We took things so far that we started to call Galileo x Danehill "a nick." The common ancestor, Northern Dancer, is 3x4, and somehow, we think this is fine. 2x3 used to be called a close inbreeding, avoided in almost all pedigrees, not even in the majority. And nicks, as we have demonstrated, used to be ten to twenty different generations. Now, a 3x4 inbreeding is called a nick and is highly sought-after.

6. Perspective distortion

All previous points describe factual events in pedigrees or within the scale of bloodlines. All data I presented are grounded in statistical analyses. This last part of the article targets our human mind and the way we are absorbed by the surrounding events.

One curiosity hit me a few years ago: during the 20th century, no European sireline could keep the leading sire's title for more than three years - neither in France nor Great Britain & Ireland. In France, Northern Dancer broke this rule four times since 1991 before overtaking for good in 2016. And the British Isles saw no other champion sire than some Northern Dancer from 1990 to 2021. It means for THIRTY years in a row - after the previous rule "no more than three times."

Even this vague comparison indicates that what we see nowadays is not exactly a normal state of affairs. But the horse-racing business seems to like records, and except for counting the impressive consecutive years of Sadler's Wells's and Galileo's reign, we celebrate, for example, Galileo's Derby winners. The recent Facebook posts made me count Derby victors of both titans, including their descendants, e.g., sons of Montjeu. The count of the Derby winners descending from Sadler's Wells now stands at 15 winners from the past 23 runnings - and this is another impressive yet absurd number:

During the entire 20th century, only two sirelines won the Derby in more than two consecutive years. It was Blandford thanks to Windsor Lad, Bahram, and Mahmoud in the 1930s; in the 1990s, Commander In Chief, Erhaab, and Lammtarra won for Northern Dancer. But since Oath's victory in 1999, Northern Dancers lost the Derby only three times, including a 16-edition winning streak from 2007 to 2022.

Finally, let's make the most specific comparison: not of yearly statistics and races but of sires.

The following table presents leading British sires of the 20th century - the ones with complete European careers, to ensure "fair access" to the production of local classic winners. The table includes legendary stallions, dynasty founders, hegemons of their times like Hermit or St. Simon. Still, you can see: the long-standing average count of classic winners for the entire stud career of the leading sire was about 10.

Galileo's count of classic winners is 41. There are no words for how much it is out of proportion to the entire thoroughbred history.

The problem is, we embrace this situation as something completely normal.

For a long time, the synonym of success for a stallion was siring a classic winner. And we can see why it was this way, right in the table: even the legendary stallions sired only a handful of them! Most of them had a classic winner in about every two crops, and "common" successful stallions had even far less than that: Great Nephew sired Grundy, Shergar, and two others; so did Aureole and Crepello. Charlottesville could sire two classic winners, Court Martial just one.

Now, after the era of Galileo, we got used to counting classic winners in TENS, without even thinking how ridiculous it is. And we also keenly celebrate any new records on stakes or Gr.1 winners, like Frankel's recent 100 group winners in the fastest time ever - while most historical stallions had about 20 or 30 of them in a lifetime.

Of course, everybody breeds for success - what is horse-racing itself, other then attempts to find the fastest horse? Or, at least, to get something in return for the horrendous stud fees. But something feels unreal about Galileo's career. The thoroughbred, as a breed, just never worked this way.

And neither did any stallion you can name - St. Simon, Blandford, and Hyperion included, and we can never find more relevant examples. In fact, not even Danehill or Green Desert fit the new pattern: Hyperion had 10 classic winners from roughly 500 foals, while Danehill needed twice as many foals to achieve the same goal!

I'm aware that it's impossible to tell breeders: "Stop breeding for the best results." However - that's what breeders were doing throughout history, and the 1950s Derby winners were, according to their bloodlines, two St. Simons, Cyllene, Nasrullah, Sundridge, Galliard, two Blandfords, Pharis, and Hyperion. Are we truly doing the same thing...?

According to the unofficial public resources, Galileo didn't sire just 41 classic winners but also more than 3,000 foals. We have ongoing discussions about mare cap rules, and whether you like them or not, they already proved one thing true: without a talent of a stallion, unlimited books of mares are of no help. Fusaichi Pegasus was a prime example of a stallion with hundreds of mares who couldn't get many big winners or a successor in the U.S. And listing through the Jockey Club data reveals far more attempts to promote stallions incapable of siring the top progeny.

As for Galileo, he just seems to be the opposite extreme: an example of what happens when there are no limits for an exceptional sire.

There's a stunning matemathics behind Galileo's numbers, though. With 41 classic winners out of 3000 foals, he sired about one classic winner from 100 foals. Hyperion had 10 classic winners among 500 foals: you do the math.

In fact, when we compare Frankel, Galileo and even Sadler's Wells to historical giants, ti doesn't seem that we're seeing "all time greats" at all: while Nearco and Hyperion had a stakes winner in one of every five foals, Galileo needed 9 foals to produce one! And while old warriors needed 50-70 foals to sire a classic winner, the "record-breaking" Frankel needs 2-3 times as many foals:

One only has to wonder why is the current racing public so blind to these facts. Unlike pedigree analyses, this is no rocket science... And it's quite shocking that this pure ignorance, on both professional and fan sides of the breeding business, is dragging us to a potential disaster.

European contexts

I didn't intend to comment on the breeding itself in this article, but it is possible to support the vague events mentioned in the previous section with current data. I've mentioned already that 78% of successful European Group runners are Northern Dancers, and so are 76% of Group sires. More specifically, 19% of current European top Group performers are Galileos, and you can't be surprised by my words that it's disproportionate again - to both Group population and the remaining 25 bloodlines. Not to mention the sheer absurdity of such number for a "bloodline in the making," which exists less than 20 years.

There are other numbers I can't resist to mention. Galileo's closest competitors are Green Desert & Danehill, with 17 and 15% of top Group runners, respectively. You may wonder where they got their numbers from since Galileo is "the designated problem" here, and so did I. The explanation deserves to be published:

Both titans were born in the 1980s, thus about 2 equine generations earlier than Galileo. Danehill needed twice as many Group stallions as Galileo, descendants of twelve different sons (!), to get barely within view of Galileo in the 2022 statistics. And for Green Desert, it took three generations of his descendants and even significantly higher numbers of foals per season for his stallions to get even with Galileo and his sons.

I avoided mentioning the US statistics, but to provide one more measure, let's take a look at Tapit. He's from the same generation as Galileo, with a similar type of influence (sire + his sons), and he's one of the dominant powers in American breeding. Still, Tapit could achieve only 7% of American top Graded runners in the 2022 season, and he's not even a leading bloodline. Which couldn't reach 10% of local bloodlines anyway.

One thought runs through the text and deserves to be said aloud: it's for the first time that we have to deal with such dominance - of both Galileo & Northern Dancer. It's a common human experience that the first tries are rarely successful, and we are certainly allowed some delay in recognition or even mistakes when dealing with the situation.

However - we will hardly have any excuse for closing our eyes.