Study Finds Maternal Cells Persist in 70% of Children's Brains for Decades
Updated
Updated · Livescience.com · Jul 19
Study Finds Maternal Cells Persist in 70% of Children's Brains for Decades
1 articles · Updated · Livescience.com · Jul 19
Summary
Out of 37 mother-child pairs, researchers found maternal DNA in 26 children's brains, showing the cells can remain from infancy into the teen years and likely longer.
Using surgically removed brain tissue from epilepsy patients, Sami Kanaan's team detected an average of 2.2 maternal cells per 100,000 cells, with one hippocampus sample reaching 459 per 100,000.
Single-nucleus RNA sequencing showed the maternal cells had matured into working brain cell types, including neurons, microglia, astrocytes, oligodendrocytes and endothelial cells.
In 32 people without known neurodevelopmental conditions, 25 had foreign brain cells — including a man in his 90s — suggesting the phenomenon is common and can persist for decades, though maternal origin was not confirmed there.
The preprint has not been peer-reviewed, but outside researchers said it extends evidence that microchimerism is a normal feature of mammalian biology and may matter for healthy brain development.
Are a mother's cells in her child's brain a lifelong gift for repair or a potential trigger for disease?
Why do maternal cells build a young brain as neurons but later become its immune watchdogs?
Beyond Individuality: The Discovery of Maternal Microchimerism in the Brain and Its Implications for Medicine and Self
Overview
A recent breakthrough in human biology has revealed that during pregnancy, cells are exchanged between mother and fetus, with maternal cells crossing the placental barrier and integrating into the child's tissues, including the brain. Remarkably, these maternal cells can persist for decades, meaning every person carries a small population of their mother's cells. This discovery challenges the idea that each person is a completely separate biological individual. The persistence of these cells highlights pregnancy as a natural experiment in immune tolerance and opens new questions about how our bodies are shaped by this lifelong cellular connection.