Dwarf gene

[Skylight_minis]

What are the chances of a horse producing a dwarf, that has tiny tim in their pedigree 10 horses back?

 

[Maple Hollow Farm]

without testing, pretty much any horse has a 50% chance, you just cant know if each horse since has passed down a gene or not. There is a test now though that will tell you for sure if your horse is carrying any of the common and currently testable dwarf genes. A little pricey but worth testing as you can afford if using a horse for breeding.

 

[Rocklone Miniature Horses]

What maple said.

How come?

 

Since Tiny TIm is 10 generations back, I think it would be more interesting to see what other "known" dwarf lines might be present.

Remember, Tiny Tim threw the gene into each breeding, but offspring of a non-dwarf carrier mare would only have one dwarf gene. Then with that horse being bred, there would only be a 50% chance the gene was passed while the other 50% of those offspring would not be carrying the gene at all to pass on.

Statistically, if there were no other dwarf carriers in the lines for 10 generations, I would not believe it would be a 50% chance the gene has passed through 10 generations with out-crosses to non-dwarf carriers. I'm too tired to "work the numbers" but I think it would be quite remarkableto think the gene passed through 10 generations. But it's certainly not impossible. But I would think the "odds" are against it being a true 50% chance after 10 generations.

Certainly willing to stand corrected JMHO ~~Diane

 

[Rocklone Miniature Horses]

Since Tiny TIm is 10 generations back, I think it would be more interesting to see what other "known" dwarf lines might be present. As statistically, if there were no other dwarf carriers in the lines for 10 generations, I would not believe it would be a 50% chance the gene has passed through 10 generations with out-crosses to non-dwarf carriers. That would be quite remarkable, but certainly not impossible. But I would think the "odds" are against it being a 50% chance. JMHO ~~Diane

But, since he is so far back its hard to know if his genes are effecting any with dwarfism. It takes two to tango, so maybe whoever has been breeding has been lucky.

 

I guess what I'm saying is that the direct offspring of Tiny Tim each carried a dwarf gene since he was a dwarf himself -- having 2 dwarf genes -- so giving one to each of his direct offspring.

In the next generation, if the direct offspring were bred to non-carrying mares/stallions, only 50% of them would statistically receive the gene, so even though Tiny Tim was only 2 generations back at that point, only 50% of that line would be carriers, the other 50% would be non-carriers.

So, yes, it could happen that one gene passed through 10 generations and would be in her horse's lines, but I would be more concerned that it could have been passed along if there were other known carriers in the lines closer than 10 generations back.

 

[Minimor]

Diane is right --there is always the chance that a mini carries a dwarf gene (until testing proves otherwise) but in this case if the horse does have a dwarf gene, it didn't necessarily carry all the way down from Tiny Tim. In 10 generations it is likely there were at least one or two other dwarf carriers in play.

 

[Rocklone Miniature Horses]

Ahh I get ya

I'm not very good at maths

 

[Silver City Heritage Farmstead]

Just a quick comment.

In the example Diane used above, please do remember that the 50% chance of passing on a dwarf gene IS FOR EACH BREEDING.

What that means is the counter (so to speak) resets at each breeding. If you have 10 breedings to a carrier, you could end up with 0 carriers--or 10. Just because a repeat breeding of our example of 10 has already produced 5 dwarf carriers does NOT guarantee the following 5 will be dwarf free. The gene wasn't "used up" in the first 5 breedings, and each breeding thereafter still has a 50% chance of passing on the dwarf gene.

That's why breeding is such a crapshot. With testing now available, why risk rolling snake-eyes and losing your investment?

 

[Rocklone Miniature Horses]

Absolutely. Not heard of many uk dwarves or lines. Any you know of?