The Rh Negative Blog

Is being left- or right-handed genetic?

My answer is “no”:

When did you first realize/decide that you were left- or right-handed?

In about 21% of identical (monozygotic or MZ) twin pairs, one twin is right-handed and the other is either left-handed or ambidextrous. Since identical twins share identical genes, this is evidence that handedness is not a totally genetic trait. … But about 17% of all twins are left-handed.

Many of the Rh negative celebrities are also left-handed:

The question is “why?”.

What else do Rh negatives tend to have in common that might contribute to this?