Horned/Polled DNA Testing

[Cascade Meadows Farm - Kirk]

Horned Dexters and polled Dexters are both GREAT! and breeders get to choose what's best for them. But wouldn't it be wonderful if we had some DNA testing available to help us identify recessive hidden horned genes?

The purpose of this thread isn't to discuss the merits of horned vs. polled (I understand that those postings belong in the polled section of the board). Rather, the purpose of this thread is to simply discuss the technical feasibility of a DNA test that identifies hidden horn genes.

I made a recent posting in the polled section, that discusses how the horned/polled genes likely work. But here, I would like to discuss our technical ability to test for those genes to find the hidden recessives.

While the exact location of the gene has still not yet been found, it has been located near the top of cattle chomosome #1. There is a method that can be used to identify markers connected with this gene locus to determine if the animal likely carries a hidden copy of a horned gene inherited from a heterozygously polled parent, or whether the animal is homozygously polled.

Such a dna test relies on studying the markers in a family of cattle, or in an entire breed of cattle. A decade ago, Gabriella Nanci worked with Bovican DNA labs in Canada to establish polled/horned testing for her family of cattle and it works with reasonably good accuracy. Every breeder in Dexters could individually work on such tests for their own family of dexters, but why not work as a group to develop a breed-wide test?

Currently, Igentity DNA lab has developed horned/polled testing for entire breeds of cattle including Charolais, Gelbvieh, Hereford, Limousin, Simmental and Shorthorn breeds. The testing is breed specific and very accurate. They say they are working on preparing the test for additional breeds.

I would like to see the Breed Association(s) work with these testing labs to get this test in place for Dexters. Does anyone know of any efforts to work with labs to implement such a test for Dexters?


www.igenity.com/beef/profile/HornedPolled.aspx


homepage.usask.ca/~schmutz/polled.html


Does anyone know where we stand with this as a Dexter breed?







PS. When we sell bulls on our farm, some buyers wouldn't mind having occasional horned calves. I like to give those buyers heterozygous polled bulls so they can have both horned and polled caves and can decide whether they want to continue with mix, or go one way or the other, so this DNA test is NOT about eliminating horns from a breed, it's about understanding hidden recessive genes to help breeders achieve their particular horned/polled goals.

[legendrockranch]

Hi Kirk,

I know the University of Queensland was working on a test about 2 years ago. I had heard it wasn't to successful though.

You might want to contact Marg Rawlings to see what see knows where the testing stands now.
www.dexterbeef.com.au

Please let me know if you find out anything as I would like to participate in the program if possible.

Barb

[wolflog]

Kirk, with your Bloodline being strong on the Belle Fourche Bloodline. You can contact Gabriella and see about if she can compare DNA alleles(sp) to her Bloodline and she may be able to tell you what you have Hetero vs. Homozygous. It works I can tell you that much, but the scientific & genetic part she would have to feel you in on.

[Cascade Meadows Farm - Kirk]

Nov 3, 2012 22:33:00 GMT -5 wolflog said:

Kirk, with your Bloodline being strong on the Belle Fourche Bloodline. You can contact Gabriella and see about if she can compare DNA alleles(sp) to her Bloodline and she may be able to tell you what you have Hetero vs. Homozygous. It works I can tell you that much, but the scientific & genetic part she would have to feel you in on.

Thanks for that pointer. I am aware of Gabriella's process as we purchased one of her first young red polled bulls (Belle Fourche Frazier) to be tested as homozygous polled about 9 years ago and indeed, he has thrown many, many polled calves born to horned cows (we sold him a few years ago and we're now using a shorter/thicker/and even friendlier son named Cascade's Bracken)

I've understood the process that Gabriella uses and have thought about doing it myself for years (building off of the good work Gabriella has done), but that process (or a very similar one) can be developed breed-wide so everyone can enjoy the benefit if we work with a DNA testing lab to help them establish a horned/polled test for the Dexter breed (as several other breeds have done).

So rather than just figuring it out for my herd, I'd like to encourage the association(s) to work with a testing lab in an official manner to establish the official test for our breed.

It would be nice if we had a single lab to do ALL of our testing, so we could send in a single sample and select the desired tests including a horned/polled dna test, and any other tests we desire.

[legendrockranch]

Kirk,
At one time the ADCA was looking into a test for polled through Texas A&M, I'm not sure what exactly happened but it went nowhere. It was either the funding or possibly the whole board was not in consensus. To top that off some people just didn't want any money going into a test that would not benefit the breed as whole.

Maybe one of the other forum members could enlighten us more or you could contact Pam M. she would know what happened.

I brought the subject up to Dr. Cothran when he was a speaker at one of our AGMs. It can be done.

Barb

[indexters]

I think it is great we have a test now.