Obama and President Bush are 10th cousins, once removed, linked by Samuel Hinkley of Cape Cod, who died in 1662.

While family trees such as these throw up interesting histories and links, genetically they are meaningless. While children carry half the genes of their father, cousins as far removed as Obama and Bush would have no more genetic link than someone they bumped into at random in the street.

Bush connection: McCain is a sixth cousin of the first lady, Laura Bush. ‘The Guardian 2008’