Cells from grandparents live on in you and appear to influence your future health Halfpoint Images/Getty Images
IN THE 1990s, Diana Bianchi at Harvard University and her colleagues made a peculiar discovery. They found that women who had given birth to boys up to 27 years earlier still had their sons’ cells circulating in their blood. “We were very surprised – it really changed our thinking about pregnancy,” says Bianchi, who is now director of the US National Institute of Child Health and Human Development in Maryland.
Other groups later found mothers’ cells in their children’s blood, even when the children had become young adults. Together, these findings suggest that while we are in utero, a small proportion of our cells cross into our mothers and vice versa, then stick around for decades.
But this goes even further because it is thought that we also harbour cells from older siblings, uncles, aunts and grandmothers. One study of 154 Danish girls, aged 10 to 15, found that 14 per cent of them had male cells circulating in their blood. This was more likely to be the case if they had an older brother. This could occur if a mother absorbed cells from her son while he was in utero, then passed those cells on to her daughter during a subsequent pregnancy. In theory, if the daughter later passed her brother’s cells on to a child of her own, that child would carry their uncle’s cells.
Such effects can also be seen…
