Handedness—as in right handed or left handed—is genetic. But there is no "left handed gene" as such. Handedness, like many other characteristics, is determined by a combination of genetic factors.

To say that left handedness is a matter of choice and cannot possibly be genetic unless one can show a specific "left handed gene" indicates that the person who makes that sort of claim doesn't know diddly-squat about genetics.

And it's interesting to note that young left handed children who are forced to learn to write and do similar tasks with their right hands rather than their left often develop a range of problems, such as stammering.

Not unlike same-sex oriented people who have "cured" of their "abnormality" by "counselors," frequently with aversion therapy.

Don Firth