Genes, on their own, cannot accurately predict handedness. Identical twins who have the same genes can have different dominant hands. Thus, left-handedness is only partially genetic. That being said, the chances of being left-handed increases if one of the parents is a lefty.
Scientists still haven’t figured out the exact reason why some of us are lefties. Several theories have been put forward including one that looks at competition and co-operation.
Left-handedness is not fully genetic. In fact, we don’t know the exact reasons.
