The Ultimate Horse
worksinprogress.co
worksinprogress.co
In humans, enlargement of internal organs (including heart) is know to be a side effect of using growth hormone as a PED. Wiki says [0] that "Extracted growth hormone was used since the late 1950s", so in 1973 it was already a well known technology.
[0] https://en.wikipedia.org/wiki/Growth_hormone_therapy#Extract...
No, Occam's Razor suggests the simplest possible explanation. To suggest that they figured out how to dope horses in 1973 and then promptly forgot how for the next fifty years is a complicated explanation. The simplest explanation, the Occam's Razor explanation, would just be that it was a fluke of nature.
Maybe anti-doping rules enforcement became stricter?
Horse doping is old. Schwarzenegger was doped up and winning in 1968+ so the science was there.
The idea that someone wouldn't dope up a horse for a marquis event like this is absurd. And once Secretariat became that famous, nobody across the industry was going to kill the golden goose by pointing out doping.
However, the window was narrow. New tests came online in the mid 1980s to detect horse doping.
The fact that nobody has been able to get even close to Secretariat's times given significant advances in nutrition and training is extremely suspicious.
> Even so, the prospects for exceeding current records through gene editing are slim. Today’s racehorses are already tightly optimized for speed, balancing strength against the cost of carrying additional muscle mass. Adding more muscle is relatively low-hanging fruit, and if this were the key to unlocking greater speed, selective breeding would likely already have brought it about.
It's a whole new tool in the toolbox, and can introduce mutations that didn't first arise by chance in order to be then spread with selective breeding.
The reason being that breeding is akin to black-box optimization -- it doesn't concern itself with genomic details at all, the phenotype being the optimization target. If we want to do gene editing directly on the other hand, we need to have some way of mapping a genotype-level edit to a phenotype-level effect.
The first CRISPR racehorses edited MSTN, which is the single best-understood speed locus because centuries of breeding already sorted it. Thus: we had a population that was varying at the MSTN gene site -> regressing by performance on the sequenced genomes of those horses flagged this site -> CRISPR was able to make a targeted edit there. Ideally we need naturally occurring, phenotyped variation to find sites worth editing.
Notice how this confines gene editing to spaces where we have confirmation that a genetic site affects the wanted phenotype. Entering a new trait-space is hard. So to your point that gene editing can introduce mutations that didn't first arise by chance: I think it's true, but novel mutations are precisely where we don't have any data (and any one experiment takes years and is very expensive).
Gene editing today is successful in specific research areas: polled cattle, PRRS-resistant pigs, disease knockouts, etc... These are places where the mechanisms that the gene-editing is supposed to target are well understood (theoretical machinery is more built out here).
Dog breeding is much worse. There are many dog breeds that are barely functional.
AKC breed notes: "Because of their front-heavy structure, Frenchies cannot swim and should never be left unattended near a tub, pool, or body of water. Like all flat-faced breeds, Frenchies are prone to breathing problems and do poorly in hot or humid weather. Flat-faced breeds are also more sensitive to anesthesia. Frenchies occasionally have eye conditions such as cherry eye, juvenile cataracts, or entropion, and skin allergies and autoimmune skin disorders also are known to occur."
They don't need much exercise, which apparently makes them popular. If you get an intelligent, robust breed such as a border collie or a Doberman, you have to get serious about training and keep their mind and body occupied.
[0] https://knowablemagazine.org/content/article/technology/2026...
[1] https://www.wired.com/story/cloning-came-to-polo-things-got-...
What about hippogriffs?
Asking for a friend...