Preimplantation Genetics: Hope for those with Lethal Gene Mutations

BOSTON, MA -- Couples, wherever they live in the world, are interested in having children who are healthy. Unfortunately all of us carry potentially lethal gene mutations, but it isn’t until we have children of our own who have a disease that we become aware of them, said one of the world’s experts in the field of preimplantation genetics at the American Association of Clinical Endocrinologists 19th Annual Meeting and Clinical Congress.

In his talk, “Embryonic Stem Cells and Preimplantation Genetics,” Mark R. Hughes, MD, PhD, told AACE delegates that until very recently, only conventional choices existed for couples who knew they carried gene mutations: adopting “which is a wonderful choice,” using a gamete, a sperm or an egg from someone else so that the child would not have the disease, “but then it’s not their biological child,” or not having any more children at all.

Now, they can use embryo testing to identify which embryos are free of lethal inherited disease, “and they can start their pregnancy on day one knowing that it doesn’t exist,” he said.

The technology is readily available now all around the world and is covered by insurance in many places. It can be done in a clinical laboratory, not a research laboratory with approaching 100% diagnostic accuracy, he said.

Preimplantation embryo testing is being used to help families conceive children who will be born to save their brothers’ or sisters’ lives. The idea is called “sibling savior” and Dr. Hughes confessed that he was uncomfortable with the concept at first.

He visibly moved his audience when he recounted how he changed his mind about sibling savior.

“A couple wanted a second child to cure their firstborn, who was dying from an inherited disease. I became concerned that the second child would be a commodity to cure the first and set out to debate the ethicality of doing this with bioethicists around the world,” he said. “One day, the father came to me while I was working in my lab. How he found me I don’t know. He said to me, ‘While you’ve been running around the world, sitting around mahogany tables debating the bioethics of this, my daughter is dying. Give us a break. People have children for all kinds of reasons, they have them for companionship, to hold marriages together, or at least try, they used to have them to work on the farm, and most of the time they have them by accident. What’s the matter with us having a child that we’re going to love very very much who also has the miraculous power of saving his or her sister’s life? How can that be wrong?’”

Dr. Hughes was persuaded. “They made a very poignant argument that they are going to love the second child every bit as much as any parent loves their second child. They are not just having the child to save the first. But they also can save the child they have and what parent would not want to do that?”

He does, however, draw the line at sexing an embryo, a practice he calls disgusting.

“Last time I checked, your gender wasn’t a disease; there’s no pathology here, there’s no pain and suffering and there’s no reason for doctors to be involved, end of discussion in my opinion.”

Dr. Hughes concluded by expressing these new technologies will be pursued in an ethical and responsible way.

“Maybe, as thinking leaders of medicine and as bioethicists and public policy leaders and religious leaders and scientists, we can carefully and responsibly move this technology from the bench to the bedside in a truly ethical manner.”