(New Scientist) – Most people seem to have cells that crossed the placenta from their mother into their developing brain in utero, even if they’re now in their 80s

Cells from your mother may have penetrated your brain when you were a fetus. These alien, or “microchimeric”, cells then seem to take up residence and perform a range of jobs, even into old age.

The discovery shows that “every human brain is likely a genetic mosaic of more than one person”, says Hina Chaudhry at the Icahn School of Medicine at Mount Sinai in New York, who wasn’t involved in the research. (Read More)