A recent study revealed that fetal DNA can last in a mother’s brain for decades. The study, which has been featured on several news reports, also found that mothers who had male DNA (from their sons) in their brains were less likely to have Alzheimer’s disease.

Researchers examined the presence of male DNA in the brains of mothers who had died between the ages of 32 and 101. Because of the Y chromosome, it’s easier to distinguish sons’ DNA in their mothers’ brains, compared to that of daughters. Male DNA was found in the brain of a woman who had died at 97 years old–evidence that fetal DNA can persist in the mom for decades. Many of the women had developed Alzheimer’s disease later in life, but less women who had male DNA in their brains developed the disease, which suggests that male DNA may have a protective role in the brain.

Fetal cells and DNA can pass the placenta and enter the mother’s bloodstream. This is the basis for DDC’s non-invasive prenatal paternity test, which detects fetal DNA circulating in the mother’s blood. During pregnancy, the blood-brain barrier is weakened, and some of the fetal DNA and cells may enter the mother’s brain, remaining there for the rest of her life.

For more information about our paternity testing options, visit our paternity testing page or call 1-800-613-5768.