What makes a person left or right handed?
Jakob Orlebeke et al at Free University in Amsterdam postulated in 1996 that handedness is random, except in the presence of a single gene called right-shift (rs). If the wild type (rs+) allele is present, the person will develop a right-handed (RH) preference. A study was performed on 1700 Dutch families containing a pair of twins (monozygotic or dizygotic, female or male). To determine handedness, both the parents and the twins were asked, “Do you consider yourself predominantly right-handed or predominantly left-handed?” Intense statistical analysis was performed to find some indication of genetic inheritance. Of the twins born to two RH parents, 12.9% were LH. Whereas, 23.5% of the twins born to two LH parents were LH. If one parent was LH and the other was RH, the twins were 25% more likely to be LH if their mother was the LH one. These data suggest a strong genetic basis or handedness, possibly due to a gene inherited from the mother. Orlebeke also observed that twins subjected t
