If you're a woman who has been pregnant with a male fetus, you may have male DNA permanently in your body, according to a study that found such genetic material in the brains of women.
The study, published in PLoS ONE, is the first description of male
microchimerism in the female human brain. Microchimerism is when someone harbors cells that came from a genetically distinct individual. Or, in the immortal words of the Monkees (singing a Neil Diamond penned song), a person can be A Little Bit Me, A Little Bit You.
The serious side of this is that scientists working at the Fred Hutchinson Cancer Research
Center have linked the phenomenon to
autoimmune diseases and cancer, sometimes for better and other times for
Lead author William Chan, who is in the Department of
Biochemistry at the University of Alberta, conducted the research while
working in the lab of J. Lee Nelson, a
member of the Center’s Clinical Research Division and a leading
international authority on microchimerism.
The scientists believe it is likely that fetal cells frequently cross the human blood-brain
barrier and that microchimerism in the brain is relatively common. Until
this study, it was not known whether these cells could cross the
barrier in humans.
According to a press release issued by the cancer center:
"Currently, the biological
significance of harboring male DNA and male cells in the human brain
requires further investigation," Chan was quoted as saying in the release.
Prior research does, however, suggest that women who harbor male DNA might be protected against some types of cancer, such as breast cancer, and
autoimmune disease, like rheumatoid arthritis. It may, though, increase the risk of other cancers, such as colon cancer.
Many studies suggest that just having a child affects the future health of the mother, and not just because the kid could drive her crazy or, conversely, help to improve her lot in life. At least mothers now know that their sons might not ever fully leave them, even after they move out of the nest.
(Image: Taylor Schlades)