A recent Radio Four programme had a distinguished retired geneticist, who is also a devout Christian, pondering the virgin birth. Jesus, it turned out, is something of a biological conundrum. As a male, he must have carried a Y-chromosome, which can be transmitted only by the father's sperm, yet apparently he had no corporeal father. Where, then, did his Y-chromosome come from? The geneticist suggested that one of Mary's two X-chromosomes might have carried a piece of the Y. Asked whether this would make Mary abnormal, the geneticist changed the subject. He did so for good reason: this condition, sometimes seen in humans, would make Mary a sterile male and the virgin birth thus triply miraculous.

LRB 9 May 2002 | PDF Download