test breedings

[Guest guest]

hello- i was wondering if you knew about the test breedings being undertaken

by the AMCA- the alaskan malamute club of america? In an attempt to collect

enough DNA samples to isolate the gene that produces Chd dwarfism, they are

deliberately breeding dwarves to dwarves and dwarves to carriers so they

have enough test litters to collect these samples.

 

Some of these dwarf and carrier test pups are then bred again by 9 months of

age. You can see photos of the most recent test litter at this address.

 

http://homepage.mac.com/erichadickes/PhotoAlbum.html

 

The research is being carried out at Michigan State University and is being

funded by the malamute club. Yesterday I was told by a club member who was

responsible for the fund raising that the scientists are having a difficult

time pinpointing the marker because the gene has variable penetrance

(something we've known for many years!) And the researchers told the club

they need 80 more affected pups to complete the project- that's an estimated

TEN MORE LITTERS of affected pups many of whom will be severely crippled.

(see photo at this site)

 

http://www.minnesotamalamuteclub.com/chdhist.htm

 

Last year, all 12 pups in a litter that was the result of a very tight breeding-

either

brother sister or father daughter-- died of heart disease and

immunological problems by 10 wks of age. Typically carriers and affected

dogs have other problems besides the dwarfism. The dwarfism characteristic

goes along with severe anemia and other traits.

 

 

The club members have been test breeding since the 1970s--dogs that did not

have certificates were mated to known dwarves or dwarf carriers. AT least 5

pups had to be produced out of a dwarf litter, or 10 pups out of a carrier.

Back then several breeders were required to euthanize these test litters in

order for the club to give them their clearances. The forelimbs of the test

bred pups were amputated, frozen, and sent to Washington State University

where they would be xrayed to determine if they appeared normal or were

dwarves. Depending on the number of pups produced and the results, the

'tested' dog would receive it's AMCA club clearance.

 

This disease is quite rare in the contemporary US population of alaskan

malamutes. Other breed clubs who wish to eliminate a disease by developing

a dna marker test have enough affected dogs to collect their samples in the

general population, but the malamute breeders/owners have produced only one

or two dwarfs in open breedings during the past 15 years, so they are

deliberately do these test breedings to proceed with the research.

 

If you would like more info about this project, please do not hesitate to

contact me.

 

Joanne Watkins, Ph.D