In an email, Reincarnation Experiment visitor Linda Evans wrote: "My son in his graduation picture and my father's graduation picture are so identical that when people saw my fathers picture they thought it was my son. It is very uncanny. My father is living. Is this just a case of look alike or could there be more here than meets the eye?"
Response from Paul Von Ward:
Thank you very much for your question. You have touched on central issues in the field of reincarnation research: What is the role of DNA in reincarnation? Can we separate DNA that seems to be a part of the soul genome (passed from one life to another outside the parental genome) from genes inherited from one's biological family tree?
The short answer is that we don't know. However, reincarnation theory postulates that a subject (like your son) would have some DNA-based features more like his previous incarnation (as in a grandparent or other family member) than like the same features in his parents (as in this case, you and the father). We don't know yet how the soul genome (psychoplasm) mixes with the parental genome to give these different results.
However, in your case, with the grandparent still alive, the similarities between grandson and grandfather likely result from the DNA that you directly passed on to your son from your father through the non-mitochondrial DNA that mothers transfer to their children (male and female). One does not have to postulate anything paranormal to explain the case you described.
(Click on the image above for some tentative ideas about how DNA matches could corroborate past-life matches and support the reincarnation hypothesis.)