Screening embryos to treat siblings raises hopes, dilemmas
A decade later, pediatrician John E. Wagner still remembers the international phone call that led him to pioneer a new, controversial means to treat certain serious blood diseases. In his office at the University of Minnesota in Minneapolis, Wagner listened as a man living in Italy asked for help for his child, a victim of the genetic condition known as thalassemia. Having treated other young patients who had thalassemia, Wagner knew that healthy stem cells from either bone marrow or blood in an umbilical cord could mend the child's faulty circulatory system. The child would have the best shot at living a full life if the donated cells came from a sibling who had a genetically matched immune system.