Q. A friend had her dog tested with one of those cheek-swab kits that tell you what breeds are in your mutt. Whippet and boxer were listed as the first and second breeds, but we’re sure she’s a beagle mix. Are these tests bogus?

When these tests were first marketed, veterinarians regarded them with skepticism, too. Big-boned, mastiff-like dogs were deemed Schnauzer crosses. Spotted, spaniel-eyed mixes received Chihuahua designations. It’s no wonder dog owners sometimes felt fleeced.

As more purebred dogs have been sampled, there has been less ambiguity about the genetic markers associated with individual breeds, and five years later, these tests have improved.

Still, I can see why so many owners disbelieve the results. When two different purebreds are crossed, many of the offspring will resemble neither parent. It’s hard to rely on science when our fundamental beliefs –– regardless of their correctness –– interfere with our interpretation of the results.

That said, I’m here to tell you that, despite your doubts, whippet and boxer ancestry is far more likely than you think.

Dr. Patty Khuly has a veterinary practice in South Miami and blogs at www.dolittler.com. Send questions to khulyp@bellsouth.net, or Dr. Dolittler, Tropical Life, The Miami Herald, 1 Herald Plaza, Miami, FL 33132.