IN THE Nineteen Nineties, Diana Bianchi at Harvard College and her colleagues made a peculiar discovery. They discovered that girls who had given beginning to boys as much as 27 years earlier still had their sons’ cells circulating in their blood. “We had been very shocked – it actually modified our interested by being pregnant,” says Bianchi, who’s now director of the US Nationwide Institute of Little one Well being and Human Improvement in Maryland.

Different teams later found mothers’ cells in their children’s blood, even when the youngsters had turn out to be younger adults. Collectively, these findings recommend that whereas we’re in utero, a small proportion of our cells cross into our moms and vice versa, then stick round for many years.

However this goes even additional as a result of it’s thought that we additionally harbour cells from older siblings, uncles, aunts and grandmothers. One research of 154 Danish ladies, aged 10 to fifteen, discovered that 14 per cent of them had male cells circulating in their blood. This was extra more likely to be the case if they’d an older brother. This might happen if a mom absorbed cells from her son whereas he was in utero, then handed these cells on to her daughter throughout a subsequent being pregnant. In principle, if the daughter later handed her brother’s cells on to a baby of her personal, that youngster would carry their uncle’s cells.

Such results will also be seen…