Studies of identical twins, separated to different homes at birth, show low, at most, 40%-50% inheritance or penetrance of even autosomal dominant disease or trait. This means that even if children get a dominant gene, only half will express the disease. Why is that? They have the identical genome!
Environmental exposures, diet and stress, all affect genes causing disease. Processes that turn genes on and off in response to the environment (both internal and external), called epigenetic modifications, shift gene expression. Sometimes a gene never gets turned on at all if conditions don’t engage it!
Our systems are designed so that by day, each organ does its, “job” and at night, the processes switch, even reverse in the case of a neuron, to get rid of bad receptors, excess charged particles, exuberant signalers and more as our system restores and heals from each day. It is continually responsive to our environment – at all levels (digestive, emotional, psychic, and physical action).
“Your tendency for behaviors is inherited”
Interestingly, neurologic tics, expressed mannerisms, facial grimaces, and stress-related itching patterns are all inherited. Just as interesting, your personal cognitive interests are get passed down through brain hard-wiring. Think of families that share a love for music, of racing cars, or making novel discoveries in a chemistry lab. These mannerisms and intellect show up when external influences such as diet or education resonate with them!