Final answer:
The Nash family utilized In vitro fertilization (IVF) followed by a bone marrow transplant to cure Molly Nash's Fanconi anemia, selecting an embryo that was both disease-free and a compatible stem cell donor for Molly.
Step-by-step explanation:
Lisa and Jack Nash used In vitro fertilization (IVF) to obtain compatible stem cells that cured their young daughter Molly's Fanconi anaemia. This method involves medical techniques where mature eggs are collected from the ovaries and fertilized by sperm in a lab. After IVF, preimplantation genetic diagnosis (PGD) can be used to select embryos that do not have genetic defects and are a good tissue match for an existing sibling who needs a transplant. In Molly's case, the Nash family was able to have a second child who was both free of the condition and a compatible donor for the necessary bone marrow transplant. The transplant could then be performed, which involves infusing healthy bone marrow stem cells from the donor into Molly, thereby providing her with a new and healthy immune system. Bone marrow transplants have a history of treating conditions like SCID, as seen in the case of David Vetter, the "Bubble Boy". However, the technique has advanced significantly over the years, making it a viable treatment for various immune deficiencies.
Although gene therapy is another method that introduces foreign DNA into cells to cure inheritable diseases and holds promise for treating immune system-related conditions, it was not the method used in Molly Nash's case.