The New Prospective Parenthood: When Does More Info Become Too Much?
Peggy Clark was 12 weeks pregnant when she went in for a nuchal translucency (NT) scan to see whether her unborn son had Down syndrome. The sonographic scan measures how much fluid has accumulated at the back of the baby's neck: the more fluid, the higher the likelihood of an abnormality. The technician said the baby was in such an odd position, the test couldn't be done. Clark, whose name has been changed to protect her privacy, was told to come back in a week and a half to see if the baby had moved.
"With the growing sophistication of prenatal tests, it seems that the more questions are answered, the more new ones arise."
"It was like the baby was saying, 'I don't want you to know,'" she recently recalled.
When they went back, they found the baby had a thickened neck. It's just one factor in identifying Down's, but it's a strong indication. At that point, she was 13 weeks and four days pregnant. She went to the doctor the next day for a blood test. It took another two weeks for the results, which again came back positive, though there was still a .3% margin of error. Clark said she knew she wanted to terminate the pregnancy if the baby had Down's, but she didn't want the guilt of knowing there was a small chance the tests were wrong. At that point, she was too late to do a Chorionic villus sampling (CVS), when chorionic villi cells are removed from the placenta and sequenced. And she was too early to do an amniocentesis, which isn't done until between 14 and 20 weeks of the pregnancy. So she says she had to sit and wait, calling those few weeks "brutal."
By the time they did the amnio, she was already nearly 18 weeks pregnant and was getting really big. When that test also came back positive, she made the anguished decision to end the pregnancy.
Now, three years after Clark's painful experience, a newer form of prenatal testing routinely gives would-be parents more information much earlier on, especially for women who are over 35. As soon as nine weeks into their pregnancies, women can have a simple blood test to determine if there are abnormalities in the DNA of chromosomes 21, which indicates Down syndrome, as well as in chromosomes 13 and 18. Using next-generation sequencing technologies, the test separates out and examines circulating fetal cells in the mother's blood, which eliminates the risks of drawing fluid directly from the fetus or placenta.
"Finding out your baby has Down syndrome at 11 or 12 weeks is much easier for parents to make any decision they may want to make, as opposed to 16 or 17 weeks," said Dr. Leena Nathan, an obstetrician-gynecologist in UCLA's healthcare system. "People are much more willing or able to perhaps make a decision to terminate the pregnancy."
But with the growing sophistication of prenatal tests, it seems that the more questions are answered, the more new ones arise--questions that previous generations have never had to face. And as genomic sequencing improves in its predictive accuracy at the earliest stages of life, the challenges only stand to increase. Imagine, for example, learning your child's lifetime risk of breast cancer when you are ten weeks pregnant. Would you terminate if you knew she had a 70 percent risk? What about 40 percent? Lots of hard questions. Few easy answers. Once the cost of whole genome sequencing drops low enough, probably within the next five to ten years according to experts, such comprehensive testing may become the new standard of care. Welcome to the future of prospective parenthood.
"In one way, it's a blessing to have this information. On the other hand, it's very difficult to deal with."
How Did We Get Here?
Prenatal testing is not new. In 1979, amniocentesis was used to detect whether certain inherited diseases had been passed on to the fetus. Through the 1980s, parents could be tested to see if they carried disease like Tay-Sachs, Sickle cell anemia, Cystic fibrosis and Duchenne muscular dystrophy. By the early 1990s, doctors could test for even more genetic diseases and the CVS test was beginning to become available.
A few years later, a technique called preimplantation genetic diagnosis (PGD) emerged, in which embryos created in a lab with sperm and harvested eggs would be allowed to grow for several days and then cells would be removed and tested to see if any carried genetic diseases. Those that weren't affected could be transferred back to the mother. Once in vitro fertilization (IVF) took off, so did genetic testing. The labs test the embryonic cells and get them back to the IVF facilities within 24 hours so that embryo selection can occur. In the case of IVF, genetic tests are done so early, parents don't even have to decide whether to terminate a pregnancy. Embryos with issues often aren't even used.
"It was a very expensive endeavor but exciting to see our ability to avoid disorders, especially for families that don't want to terminate a pregnancy," said Sara Katsanis, an expert in genetic testing who teaches at Duke University. "In one way, it's a blessing to have this information (about genetic disorders). On the other hand, it's very difficult to deal with. To make that decision about whether to terminate a pregnancy is very hard."
Just Because We Can, Does It Mean We Should?
Parents in the future may not only find out whether their child has a genetic disease but will be able to potentially fix the problem through a highly controversial process called gene editing. But because we can, does it mean we should? So far, genes have been edited in other species, but to date, the procedure has not been used on an unborn child for reproductive purposes apart from research.
"There's a lot of bioethics debate and convening of groups to try to figure out where genetic manipulation is going to be useful and necessary, and where it is going to need some restrictions," said Katsanis. She notes that it's very useful in areas like cancer research, so one wouldn't want to over-regulate it.
There are already some criteria as to which genes can be manipulated and which should be left alone, said Evan Snyder, professor and director of the Center for Stem Cells and Regenerative Medicine at Sanford Children's Health Research Center in La Jolla, Calif. He noted that genes don't stand in isolation. That is, if you modify one that causes disease, will it disrupt others? There may be unintended consequences, he added.
"As the technical dilemmas get fixed, some of the ethical dilemmas get fixed. But others arise. It's kind of like ethical whack-a-mole."
But gene editing of embryos may take years to become an acceptable practice, if ever, so a more pressing issue concerns the rationale behind embryo selection during IVF. Prospective parents can end up with anywhere from zero to thirty embryos from the procedure and must choose only one (rarely two) to implant. Since embryos are routinely tested now for certain diseases, and selected or discarded based on that information, should it be ethical—and legal—to make selections based on particular traits, too? To date so far, parents can select for gender, but no other traits. Whether trait selection becomes routine is a matter of time and business opportunity, Katsanis said. So far, the old-fashioned way of making a baby combined with the luck of the draw seems to be the preferred method for the marketplace. But that could change.
"You can easily see a family deciding not to implant a lethal gene for Tay-Sachs or Duchene or Cystic fibrosis. It becomes more ethically challenging when you make a decision to implant girls and not any of the boys," said Snyder. "And then as we get better and better, we can start assigning genes to certain skills and this starts to become science fiction."
Once a pregnancy occurs, prospective parents of all stripes will face decisions about whether to keep the fetus based on the information that increasingly robust prenatal testing will provide. What influences their decision is the crux of another ethical knot, said Snyder. A clear-cut rationale would be if the baby is anencephalic, or it has no brain. A harder one might be, "It's a girl, and I wanted a boy," or "The child will only be 5' 2" tall in adulthood."
"Those are the extremes, but the ultimate question is: At what point is it a legitimate response to say, I don't want to keep this baby?'" he said. Of course, people's responses will vary, so the bigger conundrum for society is: Where should a line be drawn—if at all? Should a woman who is within the legal scope of termination (up to around 24 weeks, though it varies by state) be allowed to terminate her pregnancy for any reason whatsoever? Or must she have a so-called "legitimate" rationale?
"As the technical dilemmas get fixed, some of the ethical dilemmas get fixed. But others arise. It's kind of like ethical whack-a-mole," Snyder said.
One of the newer moles to emerge is, if one can fix a damaged gene, for how long should it be fixed? In one child? In the family's whole line, going forward? If the editing is done in the embryo right after the egg and sperm have united and before the cells begin dividing and becoming specialized, when, say, there are just two or four cells, it will likely affect that child's entire reproductive system and thus all of that child's progeny going forward.
"This notion of changing things forever is a major debate," Snyder said. "It literally gets into metaphysics. On the one hand, you could say, well, wouldn't it be great to get rid of Cystic fibrosis forever? What bad could come of getting rid of a mutant gene forever? But we're not smart enough to know what other things the gene might be doing, and how disrupting one thing could affect this network."
As with any tool, there are risks and benefits, said Michael Kalichman, Director of the Research Ethics Program at the University of California San Diego. While we can envision diverse benefits from a better understanding of human biology and medicine, it is clear that our species can also misuse those tools – from stigmatizing children with certain genetic traits as being "less than," aka dystopian sci-fi movies like Gattaca, to judging parents for making sure their child carries or doesn't carry a particular trait.
"The best chance to ensure that the benefits of this technology will outweigh the risks," Kalichman said, "is for all stakeholders to engage in thoughtful conversations, strive for understanding of diverse viewpoints, and then develop strategies and policies to protect against those uses that are considered to be problematic."
If you look back on the last century of scientific achievements, you might notice that most of the scientists we celebrate are overwhelmingly white, while scientists of color take a backseat. Since the Nobel Prize was introduced in 1901, for example, no black scientists have landed this prestigious award.
The work of black women scientists has gone unrecognized in particular. Their work uncredited and often stolen, black women have nevertheless contributed to some of the most important advancements of the last 100 years, from the polio vaccine to GPS.
Here are five black women who have changed science forever.
Dr. May Edward Chinn
Dr. May Edward Chinn practicing medicine in Harlem
George B. Davis, PhD.
Chinn was born to poor parents in New York City just before the start of the 20th century. Although she showed great promise as a pianist, playing with the legendary musician Paul Robeson throughout the 1920s, she decided to study medicine instead. Chinn, like other black doctors of the time, were barred from studying or practicing in New York hospitals. So Chinn formed a private practice and made house calls, sometimes operating in patients’ living rooms, using an ironing board as a makeshift operating table.
Chinn worked among the city’s poor, and in doing this, started to notice her patients had late-stage cancers that often had gone undetected or untreated for years. To learn more about cancer and its prevention, Chinn begged information off white doctors who were willing to share with her, and even accompanied her patients to other clinic appointments in the city, claiming to be the family physician. Chinn took this information and integrated it into her own practice, creating guidelines for early cancer detection that were revolutionary at the time—for instance, checking patient health histories, checking family histories, performing routine pap smears, and screening patients for cancer even before they showed symptoms. For years, Chinn was the only black female doctor working in Harlem, and she continued to work closely with the poor and advocate for early cancer screenings until she retired at age 81.
Alice Ball
Pictorial Press Ltd/Alamy
Alice Ball was a chemist best known for her groundbreaking work on the development of the “Ball Method,” the first successful treatment for those suffering from leprosy during the early 20th century.
In 1916, while she was an undergraduate student at the University of Hawaii, Ball studied the effects of Chaulmoogra oil in treating leprosy. This oil was a well-established therapy in Asian countries, but it had such a foul taste and led to such unpleasant side effects that many patients refused to take it.
So Ball developed a method to isolate and extract the active compounds from Chaulmoogra oil to create an injectable medicine. This marked a significant breakthrough in leprosy treatment and became the standard of care for several decades afterward.
Unfortunately, Ball died before she could publish her results, and credit for this discovery was given to another scientist. One of her colleagues, however, was able to properly credit her in a publication in 1922.
Henrietta Lacks
onathan Newton/The Washington Post/Getty
The person who arguably contributed the most to scientific research in the last century, surprisingly, wasn’t even a scientist. Henrietta Lacks was a tobacco farmer and mother of five children who lived in Maryland during the 1940s. In 1951, Lacks visited Johns Hopkins Hospital where doctors found a cancerous tumor on her cervix. Before treating the tumor, the doctor who examined Lacks clipped two small samples of tissue from Lacks’ cervix without her knowledge or consent—something unthinkable today thanks to informed consent practices, but commonplace back then.
As Lacks underwent treatment for her cancer, her tissue samples made their way to the desk of George Otto Gey, a cancer researcher at Johns Hopkins. He noticed that unlike the other cell cultures that came into his lab, Lacks’ cells grew and multiplied instead of dying out. Lacks’ cells were “immortal,” meaning that because of a genetic defect, they were able to reproduce indefinitely as long as certain conditions were kept stable inside the lab.
Gey started shipping Lacks’ cells to other researchers across the globe, and scientists were thrilled to have an unlimited amount of sturdy human cells with which to experiment. Long after Lacks died of cervical cancer in 1951, her cells continued to multiply and scientists continued to use them to develop cancer treatments, to learn more about HIV/AIDS, to pioneer fertility treatments like in vitro fertilization, and to develop the polio vaccine. To this day, Lacks’ cells have saved an estimated 10 million lives, and her family is beginning to get the compensation and recognition that Henrietta deserved.
Dr. Gladys West
Andre West
Gladys West was a mathematician who helped invent something nearly everyone uses today. West started her career in the 1950s at the Naval Surface Warfare Center Dahlgren Division in Virginia, and took data from satellites to create a mathematical model of the Earth’s shape and gravitational field. This important work would lay the groundwork for the technology that would later become the Global Positioning System, or GPS. West’s work was not widely recognized until she was honored by the US Air Force in 2018.
Dr. Kizzmekia "Kizzy" Corbett
TIME Magazine
At just 35 years old, immunologist Kizzmekia “Kizzy” Corbett has already made history. A viral immunologist by training, Corbett studied coronaviruses at the National Institutes of Health (NIH) and researched possible vaccines for coronaviruses such as SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome).
At the start of the COVID pandemic, Corbett and her team at the NIH partnered with pharmaceutical giant Moderna to develop an mRNA-based vaccine against the virus. Corbett’s previous work with mRNA and coronaviruses was vital in developing the vaccine, which became one of the first to be authorized for emergency use in the United States. The vaccine, along with others, is responsible for saving an estimated 14 million lives.On today’s episode of Making Sense of Science, I’m honored to be joined by Dr. Paul Song, a physician, oncologist, progressive activist and biotech chief medical officer. Through his company, NKGen Biotech, Dr. Song is leveraging the power of patients’ own immune systems by supercharging the body’s natural killer cells to make new treatments for Alzheimer’s and cancer.
Whereas other treatments for Alzheimer’s focus directly on reducing the build-up of proteins in the brain such as amyloid and tau in patients will mild cognitive impairment, NKGen is seeking to help patients that much of the rest of the medical community has written off as hopeless cases, those with late stage Alzheimer’s. And in small studies, NKGen has shown remarkable results, even improvement in the symptoms of people with these very progressed forms of Alzheimer’s, above and beyond slowing down the disease.
In the realm of cancer, Dr. Song is similarly setting his sights on another group of patients for whom treatment options are few and far between: people with solid tumors. Whereas some gradual progress has been made in treating blood cancers such as certain leukemias in past few decades, solid tumors have been even more of a challenge. But Dr. Song’s approach of using natural killer cells to treat solid tumors is promising. You may have heard of CAR-T, which uses genetic engineering to introduce cells into the body that have a particular function to help treat a disease. NKGen focuses on other means to enhance the 40 plus receptors of natural killer cells, making them more receptive and sensitive to picking out cancer cells.
Paul Y. Song, MD is currently CEO and Vice Chairman of NKGen Biotech. Dr. Song’s last clinical role was Asst. Professor at the Samuel Oschin Cancer Center at Cedars Sinai Medical Center.
Dr. Song served as the very first visiting fellow on healthcare policy in the California Department of Insurance in 2013. He is currently on the advisory board of the Pritzker School of Molecular Engineering at the University of Chicago and a board member of Mercy Corps, The Center for Health and Democracy, and Gideon’s Promise.
Dr. Song graduated with honors from the University of Chicago and received his MD from George Washington University. He completed his residency in radiation oncology at the University of Chicago where he served as Chief Resident and did a brachytherapy fellowship at the Institute Gustave Roussy in Villejuif, France. He was also awarded an ASTRO research fellowship in 1995 for his research in radiation inducible gene therapy.
With Dr. Song’s leadership, NKGen Biotech’s work on natural killer cells represents cutting-edge science leading to key findings and important pieces of the puzzle for treating two of humanity’s most intractable diseases.
Show links
- Paul Song LinkedIn
- NKGen Biotech on Twitter - @NKGenBiotech
- NKGen Website: https://nkgenbiotech.com/
- NKGen appoints Paul Song
- Patient Story: https://pix11.com/news/local-news/long-island/promising-new-treatment-for-advanced-alzheimers-patients/
- FDA Clearance: https://nkgenbiotech.com/nkgen-biotech-receives-ind-clearance-from-fda-for-snk02-allogeneic-natural-killer-cell-therapy-for-solid-tumors/Q3 earnings data: https://www.nasdaq.com/press-release/nkgen-biotech-inc.-reports-third-quarter-2023-financial-results-and-business