The NY Times has a long article on the expanding frequency and breadth of preimplantation genetic diagnosis, or P.G.D. PGD involves removing a cell from an 8-cell embryo for genetic screening. Then if it passes, that embryo is implanted using traditional IVF techniques. The procedure costs up to $25,000 on top of the IVF treatment.
Previously, PGD had been limited to screening embryos for genetic disorders where death, severe disability, or untreatable disorders are all but certain, things like cystic fibrosis or Huntington's disease. In those situations, it's often covered by insurance. But that's the old days:
Already, it is possible to test embryos for an inherited form of deafness or a mild skin condition, or for a predisposition to arthritis or obesity. Some clinics test for gender. As scientists learn more about the genetic basis for inherited traits, and as people learn more about their genetic makeup, the embryo screening menu and its array of ethical dilemmas are only expected to grow.Well, I wouldn't worry too much about that. If history teaches us anything, it's that pursuits of genetic purity almost never result in any undesirable or unforeseen negative consequences.
“From a technology perspective we can test anything,” said Mark Hughes, director of the Genesis Genetics Institute in Detroit, who is performing P.G.D. this month for two couples who want to avoid passing on a susceptibility to breast cancer. “The issue becomes what is considered serious enough to warrant such testing and who decides that.”
The process is also difficult and expensive. P.G.D., which requires in vitro fertilization, can cost tens of thousands of dollars. While insurance companies often pay for the more traditional uses of the procedure, they have not done so for cancer-risk genes, fertility experts say. The barrier to affordability, some critics fear, could make preimplantation diagnosis for cancer risk the first significant step toward a genetic class divide in which the wealthy will become more genetically pure than the poor.
But seriously, parents-to-be who know of genetic predispositions in their family, like breast cancer, or colon cancer--like the Chicago dad whose story leads off the article--are only now beginning to discover PGD even exists. For young families, that means largely uncharted ethical and health territory.
update: the new headline for this article: "Couples Cull Embryos to Halt Heritage of Cancer"