IVF with PGD without revealing the results

Doctors are devising new ways to shield patients from information about their odds for disease as genetic testing becomes more common in IVF.

Nondisclosure PGD is mainly associated with diseases for which there is no cure. When patients know there is a treatment, they tend to want information about whether their genetic makeup puts them at higher risk for a disease.

In the October 14th issue of the Wall Street Journal an example of such a case is presented. Scientists took blood samples from a patient undergoing in vitro fertilization and cheek swabs from the patient’s parents. From those things, they created an individualized panel of genetic markers that could be used to screen the couple’s fertilized eggs, including for a specific gene mutation associated, in this case, with Alzheimer’s disease.

If the patient had just one copy of the mutation, she would develop an early-onset form of Alzheimer’s that runs in her family on her mother’s side. (The lab conducted its cheek-swab test before her mother’s death.) So the patient did not want to know if she carried the gene, yet wanted to prevent passing it on to her children.

After testing, the doctors selected two embryos that didn’t contain the Alzheimer’s mutation for implantation in the patient. They never tested the patient’s own DNA. Nor was the patient told how many of her embryos likely contained the genetic mutation. So while the patient successfully avoided learning whether she had the Alzheimer’s mutation, she was able to ensure her children definitely didn’t have it.

Researchers presented the case Monday at the American Neurological Association conference in Baltimore. It is thought to be the first instance of pre-implantation genetic diagnosis, or PGD, for Alzheimer’s disease linked to the presenilin 1 gene, also known as PSEN1. It is also one of the ways researchers are expanding nondisclosure PGD testing, which is uncommon but increasingly in demand, experts say.

At RPMG we have performed “blinded” PGS in dominant, non-curable diseases such as Huntington’s Disease. For further information please visit our PGD page.