Preimplantation Genetic Testing for Lynch Syndrome

by | Mar 6, 2019
TAGS: , , , ,

Share this!

Jean Hannah Edelstein has Lynch syndrome. She was born with a gene variant, passed down in her family for generations, which significantly raises her risk for colon cancer, ovarian and uterine cancer, and a number of other cancers. Those with Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), have a 50-50 chance of passing it on to their offspring. But in Edelstein’s lineage, the cycle stops with her. Now pregnant with her first child, Edelstein had Lynch syndrome testing done with preimplantation genetic testing (PGT) to ensure that she wouldn’t pass Lynch syndrome on to her future child.

Family History and Lynch Syndrome

Lynch syndrome has taken a toll on Edelstein’s family for generations. Edelstein lost her father to Lynch syndrome; he lost his own mother at 17. Her great-aunt, who was like a grandmother to her, died in her 80s after fighting multiple cancers for more than 30 years. Another aunt has also faced numerous cancers for the last decade.

While grieving the loss of one family member after another, Edelstein also manages her own syndrome. Since she was diagnosed with Lynch syndrome in her early 30s, she’s had an annual colonoscopy, endometrial biopsy, skin cancer check and mammogram; blood tests for ovarian and bladder cancer markers twice a year; and a full-body MRI every two years. Edelstein expects to have a preventive hysterectomy in her early 40s.

At the time of her diagnosis, Edelstein was single and not yet thinking about starting a family. Her doctor told her that when the time came, in vitro fertilization (IVF) paired with PGT could allow her to conceive a child without the syndrome.

“To be able to make the decision for my child that he won’t have to contend with this just felt right,” she says.

How Does Preimplantation Genetic Testing Work?

Lynch syndrome is caused by mutations in any one of five different genes. While one family may carry a risk-increasing mutation in one gene, another family with Lynch syndrome passes down a mutation in another gene. For that reason, Lynch syndrome testing is customized to look for the specific risk-raising mutation that runs in a particular family.

Before a clinician could test Edelstein’s embryos for Lynch, doctors analyzed the DNA of several of her family members who have Lynch syndrome to determine the causative mutation. A laboratory then developed a test for the embryos that would detect her family’s specific mutation.

Edelstein’s first round of IVF produced two viable embryos. “Because there was a 50 percent chance that they would carry the [Lynch mutation], and because we would have to pay [for Lynch syndrome testing] every time we sent embryos for a new round of testing, the odds didn’t seem good enough,” she recalls.

Edelstein and her husband decided that they would go through up to three IVF cycles before sending the embryos for Lynch syndrome testing. The first cycle produced two viable embryos. The next cycle produced five viable embryos, so Edelstein and her husband sent all seven for testing.

While there was a slim chance that all of the embryos would have Lynch syndrome, astonishingly the opposite was true for Edelstein’s embryos. “The genetic counselor called and said, ‘This is amazing.’ None of the embryos had Lynch. The odds of that are, like, one in 128,” Edelstein said.

Edelstein and her husband then had the embryos screened for any other common abnormalities, unrelated to Lynch syndrome, that might complicate the pregnancy via a different PGT test that looks at the number of chromosomes in each embryo, specifically called PGT-A. The screening removed three of the embryos from the pool. “The abnormalities were normal for a person my age,” says Edelstein, who is 37. Four viable embryos remained. Three have been stored. One was successfully implanted. Unlike Edelstein, her father and the grandmother she never met, the baby will not have Lynch syndrome.

If Edelstein chooses to have more children, she has three more cryopreserved embryos that will not require any more Lynch syndrome testing. “This is the end of the line,” says Edelstein. “Lynch has affected my family for who knows how many generations and there’s something very powerful about getting to say, ‘This is it.'”

 

To learn more about colorectal cancer and Lynch syndrome, check out these helpful resources:

Also, have a listen to the Taboo-ty Podcast episode featuring Serena Talcott Baughman, certified genetic counselor specializing in reproductive medicine at ORM Genomics (part of ORM Fertility) about PGT and hereditary colorectal cancer syndromes.

[cf]skyword_tracking_tag[/cf]

About Us

SharingHealthyGenes.com is managed and reviewed by experts in fertility genomics including fertility physicians, laboratory scientists, and genetic counselors who work in the field of preimplantation genetic testing (PGT) for inherited genetic diseases, formerly referred to as preimplantation genetic diagnosis (PGD).   MORE ABOUT US

Not Sure Where to Start?
Ask an Expert

Our team of genetic counselors is available to answer your questions about PGT.

© SharingHealthyGenes.com | Sponsored by ORM Genomics, a division of ORM Fertility