GREAT NEWS! DNA Test for Degenerative Myelopathy - Page 1

Pedigree Database

Premium classified

This is a placeholder text
Group text

Premium classified

This is a placeholder text
Group text

Premium classified

This is a placeholder text
Group text

Premium classified

This is a placeholder text
Group text

Kerschberger

by Kerschberger on 18 May 2008 - 01:05

By: Joan R. Coates, DVM, MS, Diplomate ACVIM-Neurology

We have discovered a gene which is a major risk factor for degenerative myelopathy (DM). In that gene, the DNA occurs in two possible forms (or alleles). The "G" allele is the predominant form in dog breeds in which DM seldom or never occurs; you can think of it as the "Good" allele. The "A" allele is more frequent in dog breeds for which DM is a common problem; you can think of it as the "Affected" allele.

Summary: "A" allele is associated with DM; "G" allele is not associated with DM.

 

Since an individual dog inherits two alleles (one from the sire and one from the dam) there are three possible test results: two "A" alleles; one "A" and one "G" allele; and, two "G" alleles. Summary: Test results can be A/A, A/G, or G/G.

In the five breeds we studied so far (Boxer, Chesapeake Bay Retriever, German Shepherd Dog, Pembroke Welsh Corgi, and Rhodesian Ridgeback), dogs with test results of A/G and G/G have never been confirmed to have DM. Essentially all dogs with DM have the A/A test result. Nonetheless, many of the dogs with an A/A test result have not shown symptoms of DM. Dogs with DM can begin showing signs of disease at 8 years of age, but some do not show symptoms until they are as old as 15 years of age. Thus, some of the dogs who have tested A/A and are now normal may still develop signs of DM as they age. We have, however, found a few 15-year-old dogs that tested A/A and are not showing the clinical symptoms of DM. Unfortunately, at this point we do not have a good estimate of what percent of the dogs with the A/A test result will develop DM within their life span.

Summary: Dogs that test A/G or G/G are very unlikely to develop DM. Dogs that test A/A are much more likely to develop DM. Our research will now focus on how many A/A dogs can survive to old age without developing DM and why.

The "A" allele is very common in some breeds. In these breeds, an overly aggressive breeding program to eliminate the dogs testing A/A or A/G might be devastating to the breed as a whole because it would eliminate a large fraction of the hi


SchHBabe

by SchHBabe on 18 May 2008 - 02:05

Can you post a link or bibliography to the originial research?  Where was this info published?

Yvette


by hodie on 18 May 2008 - 03:05

http://www.caninegeneticdiseases.net/DM/ancmntDM.htm

Read this carefully. It is a step, but certainly far from the total answer. Remember, often times a condition does not express itself without multiple genes being involved. More is at the link above.

 

Dr. Gary Johnson at the Animal Molecular Genetics Laboratory and Dr. Joan Coates at the Comparative Neurology Program of the University of Missouri and Drs. Claire Wade and Kerstin Lindblad-Toh at the Broad Institute of MIT/Harvard and their colleagues have identified a DNA mutation that is a major risk factor for development of degenerative myelopathy in dogs.

A DNA test will soon be available for breeders and pet owners, along with information about what the test can and cannot tell them. The test clearly identifies dogs that are clear (have 2 normal copies of the gene), those who are carriers (have one normal copy of the gene and one mutated copy of the gene), and those who are at much higher risk for developing DM (have 2 mutated copies of the gene). However, having two mutated copies of the gene does not necessarily result in disease.


yellowrose of Texas

by yellowrose of Texas on 18 May 2008 - 07:05

A step in the right direction.


by Blitzen on 18 May 2008 - 14:05

I posted this link here weeks ago. As far as I know there was not one single response to it. I'd think that every GSD breeder knowing about this test would want to have most of the dogs they own tested for this gene even if there is no intention to use that dog for breeding. I fully intend to have Blitz tested, he's a neutered pet.  I'd rather know that he is or is not at risk. If he is, then I'll be more aware of the early signs and maybe Dr. Clement's treatment schedule will be appropriate. Certainly if a dog of mine tested postive as being a carrier or of developing the disease in the future, it would be a very big factor in any decision to breed that dog.  It may not be prudent to eliminate all such dogs from a breeding program until more is known, but it certainly would be smart to not breed that dog to another with the same markers.  Another advatage to this test is that puppies can also be tested before they are placed in their new homes or retrained by the breeder. An autosomal recessive is the easiest gene to avoid or breed out; identifying it and acting accordingly is the challenge. IMO this is a huge breakthrough for the breed in general.

In the future many buyers may ask for the results of this test prior to purchasing a dog or puppy in the same way they now ask for hip and elbow information. I will certainly be one of them.


by Blitzen on 19 May 2008 - 13:05

bump


by Preston on 20 May 2008 - 02:05

K, h and Blitzen, thanks for this important cutting edge information.  It is this kind of information which gives hope that bad genes can be culled out before they debase the GSD breed any further. 


crazee4gsds

by crazee4gsds on 20 May 2008 - 20:05

Blitzen, I must have missed your original post somehow.  Thank you for the info!


marjorie

by marjorie on 04 August 2008 - 23:08

DM of the GSD is not the same DM  Dr Coates has been studying. She is studying DM in Corgis, Boxers, and Kerry Blues. ! The difference is HUGE! DR Clemmons DM Flash Test was created for the German Shepherd Dog and I hope GSD people will support the work done by Dr Clemmons and use the test designed for the German Shepherd Dog. Dr Coates did research GSDM a few years ago, and only diagnosed 3 out of 12 of the dogs in the study correctly. The research she has been doing the past few years is not and has not been on German Shepherd Dog Myelopathy. Please do not buy into the AKC-CHF hype! IMHO, they are a political organization who only fund their own group of researchers.

Marjorie
http://www.gsdbbr.org
 --> The German Shepherd Dog Breed Betterment Registry (including frozen/chilled semen database)
Please utilize this registry to ensure a healthy future for our breed!
Be PROACTIVE!
 http://mzjf.com --> The Degenerative Myelopathy Support Group

 


the Ol'Line Rebel

by the Ol'Line Rebel on 05 August 2008 - 17:08

Hello marj, great to have you here.  Been a long time.

But re:  your comments - what of the statement above saying:

"In the five breeds we studied so far (Boxer, Chesapeake Bay Retriever, German Shepherd Dog, Pembroke Welsh Corgi, and Rhodesian Ridgeback),"






 


Contact information  Disclaimer  Privacy Statement  Copyright Information  Terms of Service  Cookie policy  ↑ Back to top