Is Tongue Rolling Genetic?

Family studies clearly demonstrate that tongue rolling is not a simple genetic character, and twin studies demonstrate that it is influenced by both genetics and the environment. Despite this, tongue rolling is probably the most commonly used classroom example of a simple genetic trait in humans.

Why can't I roll my tongue?

It's long been thought that the ability to roll your tongue is a clear-cut case of genetics. ... The reason we couldn't all do it, we were told, is because it is a simple genetic trait. You had either inherited the right variant of the tongue-rolling gene or you hadn't. And if you hadn't, you would never be able to do it.

What determines if you can roll your tongue?

Most of the students raise their hands. They're wrong. In 1940, the prominent geneticist Alfred Sturtevant published a paper saying the ability to roll one's tongue is based on a dominant gene. ... If rolling the tongue was genetic, then identical twins would share the trait.