Only about 10% of people are left-handed, and this phenomenon occurs when the right brain hemisphere controls this hand more dominantly. Brain asymmetries that lead to hand dominance appear early in life, suggesting there may be a genetic link.
Authors of the paper found that at the population level, the heritability of left- handedness due to rare coding variants is low, less than 1%. They also found that a gene called TUBB4B that codes for tubulin was 2.7 times more likely to contain a rare coding variant in left-anded people than in right-handed people.