The first guest on Jim Al-Khalili’s new Radio 4 series The Life Scientific, Sir Paul Nurse, told of how he had discovered, in his 50s, that the people he thought were his parents were in fact his grandparents, & that his sister was his mother.
Sadly, not that rare a story, though it is perhaps unusual to find out so late. I am slightly surprised to learn that, until he applied for a Green Card, he had never been asked to provide a copy of his full birth certificate rather than just the shortened one which does not name the parents, or reveal that the father is unkown.
The real irony here though is that Sir Paul is a geneticist who had the facts of his own genetic inheritance concealed from him.
I found myself pondering how, or whether, the facts about the parentage of a child in a similar situation might be established by the scientific methods of today, or at any time in the past.
Imagine, for example, that small children & their putative parents had been recruited into medical studies involving patterns of inheritance in each year 1950, 1960, 1970, 1980, 1990, 2000, 2010.
In 1950 there might not have been much other than ABO blood groups to reveal that the child could not possibly be the offspring of one, or other, or both of the 'parents'.
In 2010 DNA could definitely rule out the paternity of the grandfather, but could it exclude, with certainty, the grandmother’s maternity?
