Family Uses Genetic Engineering to Save Daughter's Life

There was one way to cure Katie and allow her to live a normal life: a bone marrow transplant from a perfectly matched sibling. But Katie's older brother Calvin was not a match. They would need to give Katie another sibling. Lipton told them about a specific process that would ensure that their next child, and Katie, would share the same bone marrow DNA. To Steve, the whole thing seemed more like science fiction.

"It was surreal. I mean, I thought it was just in the movies," he said.

There were several steps, starting with in vitro fertilization to help the Trebings produce a maximum number of embryos. Then a doctor would test for embryos with matching bone marrow DNA using a procedure called preimplantation genetic diagnosis, or PGD. The test is done by pulling one cell from each embryo and identifying the ones that match Katie's bone marrow DNA.

"It seemed like a win-win situation," said Stacy.

Via ABC News here.