Mixed Feelings about Mixed Breed Analysis

By Amy Wence
In May of 2008, we had the DNA of our mixed breed dog, Comiskey, analyzed using the Wisdom Panel MX test. It was pretty simple. We made an appointment at CARE Animal Hospital in Kenosha, and they took a blood sample and sent it off to Mars Veterinary. The only information Mars Veterinary knew about Comiskey was his name and that he was a canine. They had no pictures or other identifying information given to them.
We anxiously awaited the results, and within a couple of weeks we got our Wisdom Panel report. We were very curious to find out what breeds might make up Comiskey’s heritage. We adopted him from Safe Harbor Humane Society at the age of 4 months, and everyone, including ourselves, thought that Comiskey was a German Shepherd/husky mix. However, as Comiskey started to grow, he looked less and less like a German shepherd and more like a husky/giraffe! He thinned out, his legs got longer, and he became quite tall. We started to question whether he had any shepherd in him at all.
When I opened the Wisdom Panel report, my excitement faded. We were right that he did have husky in his background, but the test was only able to detect it at the “trace amount” level. In fact, the test was only able to identify three breeds in his bloodlines, all at the “trace amount.” It detected Alaskan malamute, Siberian husky, and Tibetan terrier. I was very disappointed that there were no breeds detected at a more significant level and the Tibetan terrier seemed farfetched. According to the report, if a “trace amount” is detected, it means “there is a slight chance of seeing traits from the detected breeds.” I had a hard time with this because I felt that Comiskey exhibited some very distinct physical and behavioral traits.
So I went online to http://wisdompanel.com/ and contacted customer service about my concerns. I wanted to know how they arrived at these results and why only a trace amount could be detected. I have to say that the Mars Veterinary customer service is terrific. They promptly responded to my inquiry and put me in touch with Dr. Angela Hughes (DVM, veterinary geneticist and consultant for Mars Veterinary). Before speaking with Dr. Hughes, they requested a picture of Comiskey. They said the reason for this was “to understand whether there has been a sample mixup in the laboratory or if a computer algorithm generated breed signature mismatch is to blame.” Also, if Dr. Hughes determines that there was no mix-up, she may be able to scientifically explain some of the physical traits seen in Comiskey, based on his genetic profile. After submitting a picture of Comiskey, Dr. Hughes called me to discuss his results. She was able to take a closer look at Comiskey’s breed specific patterns, or “trees” as she called them. You see, the test works by extracting Comiskey’s DNA from his white blood cells and then analyzing it using a computer test program that forms breed-specific patterns by identifying slight variations in his DNA makeup. The confidence level of the test is to go back three generations, to the great-grandparent level. At the time Comiskey was tested, the Wisdom Panel MX was only 84% accurate for firstgeneration mutts (i.e. – 2 different purebred parents) and detected 134 AKC breeds. However, Dr. Hughes explained to me that the accuracy of the test decreases somewhat significantly with each generation of mixed breed. She told me that Comiskey’s bloodlines may be too mixed for the test to accurately identify specific breeds. When I asked about the Tibetan terrier, she said that it appeared to be a “false positive” which can occur when pushing the lower limits of detection capability, such as at the great-grandparent level.
After reviewing his “trees,” Dr. Hughes concluded that Comiskey had both husky and malamute at the great-grandparent level. She also told me th at they are planning to add more breeds to the test and that I could call back any time to ask her to take another look at Comiskey’s analysis. I was very pleased with her explanations and the level of customer service I received from Mars Veterinary. However, I was still disappointed in the test capabilities and longed to find out where Comiskey’s trademark ears came from. Then, about 6 months later, I got an email from Mars Veterinary announcing that they had just improved the accuracy of the test and added more breeds. I was very happy about this because they could now detect 157 breeds and had an accuracy of 90% for first generation mutts. I called Dr. Hughes back (she actually gave me her direct number) and asked her to take another look at Comiskey’s profile. She said that with the improved accuracy of the test, the genetic marker patterns or “trees” were now simpler and that the new analysis revealed that Comiskey does have a greater percentage of husky and malamute than originally detected. She said those two breeds could now be seen at the grandparent level, as opposed to the great-grandparent level. She also verified that the Tibetan terrier result was inaccurate and did not show up on the new analysis. I asked her if he had any Ibizan hound in his lineage because I was still trying to find out where he got those huge ears. She looked and said no, so then I asked her to check the Pharaoh hound, which is similar in appearance to the Ibizan hound. As she examined the results, I could hear her thinking aloud and to both our surprise, she said yes, that it did reveal Pharaoh hound at either the grandparent or greatgrandparent level! I was very happy to hear this because finally I knew where those rabbit ears came from!
In the end, I have to say that I was pleased with Comiskey’s DNA results. I feel more confident in the results than I did initially. I think it’s because I am more confident in having an expert veterinary geneticist analyze his genetic profile, rather than simply running it through a computer. Although, I am sure there are more breeds in his heritage, I do feel that he strongly resembles these three breeds the most, both physically and behaviorally. I think that mixed breed DNA analysis is a new and exciting technology that will continue to improve in both its accuracy and detection capabilities. To find out more about Wisdom Panel MX, go to: http://wisdompanel.com/