Umbilical cord blood donation allows a type of stem cell transplant. This is my third post specifically about stem cell transplants and ancestry testing and it’s the first that focuses specifically on umbilical cord blood. You can read the first two about a case of bone marrow transplantation affecting an ancestry test result and how to try to go about DNA testing if you have already received a stem cell donation:
The New England Journal of Medicine recently released a paper on an extremely rare set of boy/girl sesquizygotic twins. Early in the pregnancy, it was noted on ultrasound that the twins shared a placenta, indicating they were likely identical twins. Sesquizygotic twins have been reported in the literature before, but this is reportedly the first case of it being detected during a pregnancy.
When you have an allogeneic bone marrow or stem cell transplant, the blood-producing cells in your bone marrow are killed off by radiation or chemotherapy and then replaced with functioning cells from another person. The technical term for this process is allogeneic hematopoietic cell transplantation.