Veterinary Voice: Congenital and/or Hereditary Definitions

Dr. Marty Greer, DVM joins host Laura Reeves for a deep dive on the question of congenital vs hereditary disease definitions.

“So congenital is something you’re born with, not necessarily inherited, but something you’re born with. Genetic is something that you carry the DNA for,” Greer said. “If you’re born with something, it’s congenital. So, if you’re born with the umbilical cord wrapped around the puppies leg and the leg doesn’t fully develop, that’s congenital because they were born with it but it wasn’t genetic, it was an accident that the cord wrapped around the way. Just ’cause you see it at birth doesn’t mean it’s genetic.

Many diseases, Greer noted, “there is a genetic basis” with a “trigger.”

“An epigenetic or an environmental trigger, is there a nutritional component to it, was there some exposure to a chemical that predisposed the patient to it. So that’s where it starts to get muddy. Not everything that’s genetic is easy to figure out the inheritance pattern for. The things that we can DNA test for now are pretty much autosomal recessive genes,” Greer said.

“Are we throwing dogs out of our gene pool because they have something that’s genetic and we don’t have the right test for it, then we may never have a test for it or it’s not genetic or have some genetic and epigenetic and environmental component to it? As much as we think we understand this stuff, it’s not easy,” Greer added.

“The more we know, the less we know. As we start adding this information to our knowledge base, it’s going to become evident to us that what we thought isn’t really true… all information is valuable, but if you don’t apply it correctly, you’re going to end up bottlenecking your gene pool, as you’re going to throw good dogs out.”