All I can say is that after Ben, and with as many puppies as we have bred, we never saw DM again. I can't explain that, and just feel we have been fortunate. I can't put a great deal of faith in the test, but will continue to use it. How we use it, will be learned after another 20 years or so. Evan L. Ginsburg Asgard German Shepherds http://www.asgardgsd.com/ Where Type Movement and Temperament come together In a message dated 12/15/2013 2:25:20 P.M. Pacific Standard Time, cnnpmm2@xxxxxxxxxxxxxx writes: For those of you that swear by the DM test, how do you explain the cases where the dog tested DM Clear and developed DM anyway? Or, the dog that tests DM positive and never develops the disease? This leads me to believe that DM is polygenic in nature and not a simple recessive. If it is true that DM is polygenic, then, unfortunately, a *definitive* genetic test for DM will be difficult to develop. ============================================================================ POST is Copyrighted 2012. All material remains the property of the original author and of GSD Communication, Inc. NO REPRODUCTIONS or FORWARDS of any kind are permitted without prior permission of the original author AND of the Showgsd-l Management. ALL RIGHTS RESERVED. Each Author is responsible for the content of his/her post. This group and its administrators are not responsible for the comments or opinions expressed in any post. ALL PERSONS ARE ON NOTICE THAT THE FORWARDING, REPRODUCTION OR USE IN ANY MANNER OF ANY MATERIAL WHICH APPEARS ON SHOWGSD-L WITHOUT THE EXPRESS PERMISSION OF ALL PARTIES TO THE POST AND THE LIST MANAGEMENT IS EXPRESSLY FORBIDDEN, AND IS A VIOLATION OF LAW. VIOLATORS OF THIS PROHIBITION WILL BE PROSECUTED. For assistance, please contact the List Management at admin@xxxxxxxxxxx VISIT OUR WEBSITE - http://showgsd.org SUBSCRIPTION:http://showgsd.org/mail.html NATIONAL BLOG - http://gsdnational.blogspot.com/ ============================================================================