One of the most recent theories states that human beings with the negative RH factor would be part of an extraterrestrial lineage.
We know that people have four blood groups: A, B, AB and 0. The Rh factor, or Rhesus factor , refers to the presence of an antigen (protein) on the surface of red blood cells. It is a hereditary character and is transmitted as an autosomal dominant: s and a person has this factor it is said that his group is Rh positive (Rh +), if instead the protein is not present on red blood cells the group is called Rh negative (Rh- ).
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