Using research and deduction, I am re-evaluating the guess that Chocolate carries patterning genes. My question is, which ones?
To those of you that don't know, Chocolate is my solid black POA breeding stock mare. Both her parents were LP patterned. The genetics make sense as to why she is solid, but if I were to breed her back to a spotted horse, what spotting genes could she possibly contribute? The picture below gives you an idea of just how solid she is. Doesn't get much blacker n' that!
Because LP is still constantly being researched, some of my research may be proven not quite correct in several years. That's okay, just as long as you know it is an ongoing process.
From what I understand, LP is under current study. Actually, to be more precise, the patterning genes are under investigation; LP has been marked and is traceable through various tests. These tests are offered to the public, and don't cost much money. It is how the pattern genes work that stumps the researchers, and how they work with LP.
Here are several bullet points to remind you of how this works:
1. LP is the master switch. Turn it on, and you have varnish roan. This is easy to understand, but how varnish roan turns into leopard and blanket appaloosas is a matter of question.
2. PATN1 is the gene that the Appaloosa Project (the main scientists behind the discovery of the LP marker, and the current investigators) believes turns varnish roan into leopard pattern.
3. Unlike what I posted before on pattern genes, PATN1 is inherited entirely seperately from LP. The marker that is what you test for in colors has not been identified. What is odd to me about being seperate from LP is that, even though they are different genes, they still work together in a drastic way.
4. The Appaloosa Project has determined that PATN1 is dominant over whatever gene causes blanket. That means that blanket horses do have have PATN1, but leopard horses could carry the blanket gene. Whether they have one or two copies of PATN1, it still 'over-rules' the blanket gene.
5. I call the gene that controls blanket the 'blanket gene' for now. The Appaloosa Project plans on calling it PATN2, yet because it has not been identified they cannot officially call it anything.
So now, which pattern genes does Chocolate carry?
The only thing I can do is make a conclusion based on pictures and descriptions. Descriptions are hard to take seriously, since so many people don't know how to differentiate patterns. However, because I am working on patterning genes and not whether the horse is heterozygous or homozygous LP, descriptions may actually mean something. It is not that hard to tell the difference in a blanket, leopard or varnish roan, and whether any of those is snowcap or fewspot is besides the point.
The trouble with patterning genes is that the outward appearance tells us almost nothing about whether they are heterozygous or homozygous for PATN1 or the blanket gene. If a horse is homozygous LP and is fewspot, that does not mean he is homozygous PATN1. Because they are inherited seperately, he could be either PATN1/n or PATN1/PATN1, but because he is fewspot it would be impossible for him to not have any PATN1. Do you follow?
Allbreedpedigree.com is a lifesaver. It really is; I would only have two generations back on Chocolate without it. Two generations is all I really need, but it also contains some photos, and the names mean everything. Here is a link to her pedigree: http://www.allbreedpedigree.com/jkb+chocolate+bar
So now, I need to look at her parents and offspring to help determine her patterning genes, or the possibility of pattern genes. She has had one blanket foal, and one leopard foal. Because both of the stallion's she was bred to were patterned, that may or may not be important.
When I do a Google search on her dam, JK Jokerette, I don't get much. I know the breeder that owns her, and he has a descriptions of his horses on this page. To quote what he says on her, "JK Jokerette “Sweetie” ApHC 537354 mare, foaled 3/14/94 – Chestnut w/roaning and snowflakes. 14-1 hands. This is a beautiful mare with super donformation, fantastic disposition and a Who’s Who pedigree, tracing to My Secretariat, Joker B, Bold Combatant and Bold Ruler plus her dam was half Arabian. "
I think I trust his opinion on this. When he refers to roaning and snowflake, these are terms that are used in stages of varnish roan. Because varnish is always progressive, she won't always be snowflake, or she may constantly stay with the snowflake pattern.
Either way, how I come to conclusions on this is that, because Sweetie (Jokerette) is varnish, she has no pattern genes. Therefore, Chocolate inherited no pattern genes from her. That isn't really helpful, other than I know that Chocolate can't be homozygous for either pattern genes.
Now for Chocolate's sire. JKB Bold Bar. Of all the pictures on Allbreed, they are all at least three generations back. Not really helpful. Moving on to descriptions, and other progeny.
According to the same breeder's website, he still owns the sire's dam. Here is the description: 'JKB Dilly Bar – 40640 – Foaled April, 1994; black with snowflakes."
That doesn't bode well. Another varnish roan. This means that JKB Bold Bar could not be homozygous for either pattern genes. Since he was heterozygous, this means that there is a 50/50 chance Chocolate carries pattern genes. The odds are not as strong as I expected; when I went in to this research, I thought both parents were patterned.
If I only knew what pattern he was, it would rule out possibilities. If I knew he was blanket, then he would be recessive for PATN1 and heterozygous for the blanket gene. I would know this because PATN1 is dominant over the blanket gene. If he were leopard, he could be heterozygous for both.
Because JKB Bold Bar's mom is varnish and doesn't carry pattern genes, lets look at his dad, Santee Super Son. From Allbreed, we know his dam was blanket. There's a picture of her attached.
When I type in Santee Super Son as a search, I don't get anything. However, there is a link to Gene Carr's website. For those of you that don't know, Gene Carr is one of the biggest POA breeders and showers in America.
Interesting; nothing on Santee Super Son, but he has lots of stallion's with Santee in their name. I find it interesting that this particular Santee is not on his page. But wait, look at this one! On his stallion page there is a picture of Super Sun, grandfather of our Bold Bar. Great; now we have pictures of both of his grandparents. Below is Super Sun. And Here is a link to the mare he was bred to (scroll down; you're looking for R Misty Stuff)
Sadly, even though I use all my brain power, it will take more research to learn anything about these two grandparents in particular. *Sniff*. Moving on.
You know, the easy thing to do would be to just call the breeder of JKB Bold Bar and ask for pictures or a description. But this research stuff is fun!
I think the next step is to look at Bold Bar's progeny. The first one is JKB Bold Siri Delight. I can't find any pictures or descriptions on her, so moving on to the next one.
Oohh, this is interesting. Listed in JKB Bold Bar's progeny is JKB Boldbars Lucky Lady. Quite the name. Anyway, her dam is my other mare, Barbie Doll, a.k.a. Shesa Fancy Lady. Barbie carries blanket genes. So Barbie was bred to Chocolate's sire. I only have one picture of this little filly, and she appears to be blanket as well. Barbie's other son is blanket too; she might be homozygous, which doesn't give me any info on the sire. Ugh.
Oh look, JKB Boldbars Lucky Lady had two foals as well. I could examine them to try to determine whether she was homozygous for the blanket gene. If she was, that means that JKB Bold bar carried at least one blanket gene. However, because there were only two foals, it could be just chance. Ugh.
What next? Ummmm, probably a phone call. It's a simple question.
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