A new study has shown that male DNA ends up in the brain of mothers of who have a son.
Researchers said that mothers of sons, or a female who was in the same womb with a male baby, end up with male DNA deeply embedded in their brain that forever alters their health prospects.
The University of Washington scientists looked at the post-mortem brains of 59 women, reported PopSci.
It was found that 63 percent of the brains had fetal DNA that could only come from a male.
The researchers found that the genetic traces of the mother's son was scattered around the brain, particularly in the hippocampus, said the Los Angeles Times.
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The effects of the male DNA in a female brain are largely unknown but the research suggests that it may protect against Alzheimer's disease.
The study found that women who did not have male DNA were more at risk for the degenerative disease than the others, reported Red Orbit.
“To me, this suggests that the presence of fetal cells in the female brain prevents disease,” said Hina Chaudhry, a cardiologist at Mount Sinai School of Medicine, reported Wired.
Indeed, the technology magazine said that the theory is not without precedent.
A 2010 study by Chaudry and her colleagues found that fetal cells migrated to the mother's heart and helped repair heart tissue.
The new finding was published in the journal PLoS One.