My dog is extremely fearful, much more than any other dog I've owned. I've heard that anxiety can be genetic—does that mean my dog's behavior is inherited, or could it be due to how I raised him?

Could you tell me more about your dog’s fearful behavior? Please describe what it looks like.

Heritability is a population statistic. It’s due to variation genetics divided by variation due to the environment. For fear, different studies have found it to be about 46% heritable within a specific population. That means that about 54% of the trait is associated with the environment or non-genetic influences. While this is interesting, it does not mean that 46% of your dog’s fear came from their genes. They can be born with a more sensitive nervous system, more vigilant, easily startled, slower to recover, or more prone to cautious coping styles. It’s their exposure to experiences that shape them and how their genes interact with the experience.

Prenatal influences or what happened to his mother while the puppies were in utero such as maternal stress, nutrition, illness, can impact the puppies. Neonatal and early puppyhood environments also play a role, and as they grew and the sounds, people, other dogs, even the surfaces they were exposed to, all this impacted him even before you adopted your puppy and has a tremendous impact on shaping him.

Then there are the fear periods which increase sensitivity where exposure to single events of loud sounds such as fireworks or the vacuum cleaner can have an outsized impact and negative associations.

So, to answer your question about is it genetic or how your raised him, the most accurate answer is that it’s often both, an inherited predisposition and life experiences interacting that contributed to his fearfulness. The good news is that we can create a plan to work on building his confidence and help him to feel more secure in novel situations.