Another route to chimerism is through the cells that routinely pass from a mother to fetus and remain there for life.
Dr. Ann Reed, chairwoman of rheumatology research at the Mayo Clinic, who uses sensitive DNA tests to look for chimerism, finds that about 50 to 70 percent of healthy people are chimeras. The more scientists look for chimerism, the more they find it. It seemed not to exist in the past, she said, because no one was explicitly looking for small amounts of foreign cells in people's bodies.
Further, experiments in mice show that stem cells from a fetus can take up residence in the mother's body, possibly indefinitely and granting benefits:
Taken all together, these results suggests a woman might have persistent chimeric cells from any or all of the following, if including all remote possibilities:
• her own mother
• a 'vanished twin'
• a grandmother or earlier matrilineal ancestor (if those cells persisted in the mother and then also transfered to the fetus)
• older siblings (if those cells persisted in the common mother and then also transferred to the later fetus)
• her own children
• and of course, any donors from which the woman receives blood or tissue during a medical procedure
http://www.nytimes.com/2005/05/10/health/10bloo.html?_r=1...
From the article:
Another route to chimerism is through the cells that routinely pass from a mother to fetus and remain there for life.
Dr. Ann Reed, chairwoman of rheumatology research at the Mayo Clinic, who uses sensitive DNA tests to look for chimerism, finds that about 50 to 70 percent of healthy people are chimeras. The more scientists look for chimerism, the more they find it. It seemed not to exist in the past, she said, because no one was explicitly looking for small amounts of foreign cells in people's bodies.
Further, experiments in mice show that stem cells from a fetus can take up residence in the mother's body, possibly indefinitely and granting benefits:
http://www.vetscite.org/publish/items/002393/index.html
Taken all together, these results suggests a woman might have persistent chimeric cells from any or all of the following, if including all remote possibilities:
• her own mother
• a 'vanished twin'
• a grandmother or earlier matrilineal ancestor (if those cells persisted in the mother and then also transfered to the fetus)
• older siblings (if those cells persisted in the common mother and then also transferred to the later fetus)
• her own children
• and of course, any donors from which the woman receives blood or tissue during a medical procedure