Hate to burst your bubble folks but both my parents are righties and both my sister and I are lefties! So explain that!"
Read about the random recessive gene..you carry this gene and pass it gone
MOST persons prefer to use their right hand (RH) for one-handed tasks, such as writing, throwing a ball, hammering, sawing, cutting with a knife, and so on, but a significant minority prefer to use the left hand (LH) or either hand (ambidextrous). The term NRH (for non-right hander) is used here to represent both left-hand and ambidextrous users. The question of whether hand-use preference, referred to as handedness, is specified by biology/genetics, by cultural training, by pathological reasons such as birth stress, or by a combination of these etiologies has been addressed for decades and the debate continues. Several observations suggest problems with a strict genetic etiology. For example, not all the children of RH × RH are RH; not all the children of NRH × NRH are NRH; 18% of monozygotic twins are discordant for handedness even though co-twins possess identical genetic makeup; and cultural pressures can change some persons' preferences (R ife 1940). A relatively recent “random-recessive model” postulated, first, that a single hypothetical gene named RGHT1 (for specifying right handedness) is fully penetrant, causing persons with one or two RGHT1 copies to become RH; second, that the recessive nonfunctional allele r/r (r for random) homozygous persons develop as a 50:50 mixture of RH and NRH; and third, that monozygotic twins discordance results from randomness due to their r/r genotype (K lar 1996
I myself am a identical twin mixed handed my brother is mostly right handed 95 % we carry the random recessive gene which
is displayed at random when though we carry identical genes ! ~Cal
