HGG Community Forums

I love apps and have watched appy genetics discussions since long before any genetics testing was possible, so I can help with the basics. Hopefully if I've gotten any of this wrong according to more recent information, someone will correct me. :)

Blanket with spots: LP/n most often causes minimal appy markings at birth and then varnish roans to reveal more spots later. LP/n with PATN/n usually makes a true blanket with spots, though the size of the blanket is determined by some other modifier.

Leopard: LP/n PATN/n can also produce horses born with a blanket that roan to 'near-leopard' before age two, but generally it's accepted that a true leopard is LP/n PATN/PATN and will be born predominantly white with spots, sometimes with a roan head and dark lower legs that roan eventually to white with spots.

Snowcap: LP/LP makes a snowcap and can mostly hide one copy of PATN, though it will enlarge the 'snowcap'. A true snowcap will have a large white blanket without spots and is always homozygous LP.

Fewspot: LP/LP PATN/PATN is a fewspot, a white horse that has only a few appaloosa spots, often with dark feet and a darker mane and tail, sometimes with faint facial markings. Fewspots will always throw color, no matter what they are bred to.

Lightning marks: You didn't ask about these, but they are distinct streaks of white often seen on the dark lower legs of strongly spotted appaloosas. Many breeders think they are an effect of one of the as yet unmapped appy genes. No one can prove what it is yet as far as I know, but many old-school breeders consider it the marker of a truly 'loud' appy because lightning marks most often appear on horses with strong spotting genes that will breed true.

Snowflake: In this game snowflake only shows when homozygous, which makes it recessive like flaxen. In reality I've seen quite a few app crosses with snowflakes so I doubt it's truly something that has to be homozygous to be seen. As far as I know no one has ever tested an Egyptian Arab and found LP or PATN, but I've personally seen an Egyptian stud with a very pure Al Khamsa pedigree sire a snowflake filly out of a mare with a minimal frosted blanket barely the size of two spread hands over the top of her hips.

Frost: I think what you mean here is the lightly frosted blankets without spots that never change over a horse's life. Horses with a frosted blanket can throw solid or app foals so are not LP/LP like a snowcap, but they also often don't roan out more over time like a varnish app. A frosted blanket doesn't look like a normal blanket, instead appearing almost like a roan patch on the horse's hips. LP has to be present for it to show, but I don't think geneticists know what the modifier is that causes it yet.

Varnish: An effect of the LP gene governed by modifiers not yet isolated, but definitely not the same as true roan. Varnish leaves distinct dark 'varnish marks' on the head, upper and lower legs, and often the point of the hip and shoulder along with revealing permanent appaloosa spotting as the horse roans out. A varnish roan with spots will have permanent spots that don't disappear or change as they age, and though their roaning will change with the seasons and is often darker at different times of year, they become progressively more white as they age until their only dark markings are their varnish marks and any appy spotting.

True roan (Kit r) is not related to appy genes at all. It usually leaves the entire head dark, often with the lower legs also dark, sometimes with changing spots called 'corn' markings, and injuries to the horse can also cause dark markings. Darker spots on a true roan can change with the seasons and they are usually not the same every year unless caused by a scar. True roans never roan out truly white unless they have other genes along with the roan that cause them to lose color. Most true roans stabilize as far as color goes fairly young, varying with the seasons but in a predictable way.

And it's worth mentioning that grey is also not related to either LP roaning or true roan. App roaning never makes the spots roan or fade away, and though true roan does affect app spots it will usually not make them disappear completely. Grey, on the other hand, removes pigment from the entire body of the horse including any appy markings, eventually turning them white.

Gender effects Appy phenotype? Can you give examples or tell me where to search to learn more? Simply a curiousity on my part, not challenging you to prove it!

I am also interested to know how gender affects appaloosa patterning!

And yes, appaloosas (and many other patterned horses) can throw loud foals from outcross breedings simply because hidden genes are passed on instead of being culled out because the gene that turns on the expression is missing. Maybe that particular Arab didn't have phenotypically spotted horses in his pedigree, but way back when there was a horse that carried a hidden gene and passed that on. It's kind of exciting to find those solid colored horses that throw party-colored foals.

but I would think that, like PATN, it would only be found in breeds with spotted ancestors, however far back

The two mutations would have occured totally separately and at different points in history. PATN1 has been concentrated in LP breeds, that does not mean other breeds can not have it. The Arabian breed may or may not have it, but they are still distinct and unlinked genes. Don't forget though that PATN1 and LP predate domestication and the Arabian breed. There are no horses that don't potentially have spotted ancestors.

And yes spot on about the gender.

@HTRanch The Arabian stud I mentioned was from mostly bay lines with minimal white markings (spitting image of his grandsire, Moniet El Sharaf), but now you've got me curious if any others like him have been outcrossed to apps. lol

And sorry, I had this tab open in the background and thought I had hit post, but didn't. :\">

The cool thing about both genes is we have cave paintings of horses who must have had them both. It's neat to know how dang old the genes are (at minimum).

If a stallion is hom for Lp. all his foals will have at least one copy of Lp. But the expression of that pattern depends on the Patn, a copy from his sire and a copy from his dam. Since Arabians or thoroughbreds produce Lp foals when crossed with hom Lp, does this not mean that all breeds carry the patn gene, regardless of their phenotype ?

Knabstrupper, is that a different gene or just Lp with a European heritage ?

Think of PATN as sort of like a magnifier for LP. LP will show on the coat without any PATN gene, but with the PATN gene you get a bigger blanket, and with two PATN you get leopard. PATN can be carried without LP, but most breeds have bred for solid horses for so long that it's unlikely you'd find one with PATN and no evidence of LP in the bloodline. The exceptions are the Quarter Horse and Paint because there are horses in both registries with LP ancestors or who are even LP themselves, varnish roan appaloosas registered as true roans.

It's not common now with genetic testing, but back when the breeds were being formed it was very common for a 'roan' mare to have foals that went on to be in three registries even though she was truly an appy. A perfect example is Blue Vitriol. She was registered with the ApHC and the AQHA with her name spelled slightly different in the two registries, though her owners admitted it was the same mare. She was at least 50% Thoroughbred by close-up blood ancestors with many lines through them to the famous Arabian and Barb stallions who 'fathered' the English Thoroughbred: the Godolphin Arabian, the Darley Arabian, and the Byerly Turk.

That old roan mare named Blue wasn't just mostly Thoroughbred, though. She also had two close lines to the fantastic old foundation stallion Old Fred, who was called a Quarter Horse but was truly a sabino overo palomino who figured strongly in the beginning of not just the AQHA and ApHC but also the APHA and the Palomino breeders association. Old Fred was mostly Thoroughbred as well if you trace him back, with a few Standardbreds and one unknown dappled palomino mare in his close-up pedigree that gave him his famous color. Through Old Fred, Blue Vitriol had half a dozen lines to Steel Dust and Shiloh, who like most American-bred horses of the time were both also mostly Thoroughbred.

Blue Vitriol had only one line to an appaloosa through her dam, who traced back through a line of blue roans to an appy stallion called The Arab, who was by The Circus Horse, who most agree was a black leopard appaloosa. Some say The Arab was out of an Arab mare and that's why he was called that, but I've never seen anything quoted from people who actually knew the horse saying that. He was widely used in 'improving' plain mares though, and seems to have thrown more blue roan appaloosas than anything else.

Anyway. lol Most would think from her pedigree that Blue Vitriol should have produced nice solid Quarter type foals and mostly you'd be right, but once in a while she threw 'crop out' foals that her Quarter Horse breeder owners registered in the ApHC under a slightly different name to sweep them under the rug. (She was Blue Vitriol in the ApHC, and Blue Viterol in the AQHA.) You might even have heard of one of her 'crop-out' colts, he's world famous and his name is known even outside Appaloosa circles.

He was Joker B, a loud black blanket and spots colt by a solid sorrel Quarter stud from many generations of 'pure' solid Quarters. :))

Joker B, who was incorrectly labelled as a leopard by many because he roaned out young, went on to be one of the most decorated ApHC stallions of all time. He had many championships to his name and was the sire of champions in every discipline, from halter to hunter, roping to racing. Joker B earned a Foundation designation from the ApHC (F-678) and even made it into the ApHC hall of fame, and he owes it all to that blue varnish roan mare whose owners insisted so strongly that she was a Quarter Horse that they managed to get her registered as one. :D

Joker B:

A good in game example of PATN being carried without Lp would be this stud I have. He is actually homozygous for PATN (confirmed because I noticed while I was GMTing him). He has no Lp Appaloosas for several generations in his pedigree. He has some flashy spotty babies, including the horse I linked below him, who inherited Lp from his dam which allowed PATN to express.


Western Drums 9S

His flashy son:

HT Razzmatazz

This is why solid colored Apps can be really important in a breeding program if you want large blankets and spots. There is always a possibility that they inherited PATN from their parents, and if bred to a homozygous Lp mate they have the potential to produce flashy foals with both PATN and Lp.

Solid apps can be very important to a breeding program @HTRanch, and your stallion is a great example of why. :)

I know of one real life colt with one tiny fleck of white on an otherwise coal black coat who recently tested LP/LP, and a few others who carry PATN with no LP or characteristics in them or their parents, but they all do go back to an appy eventually. lol

Edit to add: :)) Forum hasn't noticed me changing accounts in weeks so I stopped checking, and now it suddenly did. Sorry. lol

I did see where UC Davis says it's been found in non-LP breeds, but they didn't give details and my Googlefu wasn't strong enough to find any concrete information of it being found in anything but LP horses in any numbers. I hope they publish the info publicly one of these days!

I know PATN is in both the AQHA and APHA, but they had foundation horses who were varnish roans with LP so it's been known to be in that gene pool for years. lol Gypsy breeders are testing for PATN as well, I know, and sometimes finding it in horses they didn't expect, but LP is commonly found in that breed too. Most of the Gypsy folks I know are using Etalon for genetics testing and doing the full panel because Gypsy horses have all sorts of interesting things in their gene pool. :)

Once upon a time I helped do some research about which breeds not seen as LP today had LP buried in their origins. The list would surprise most people! :)

lol Well, little Mesohippus and Miohippus are thought to have been spotted, but yeah. I meant breeds known today. :D