Black History Month reminds us of the heroes of civil rights in the U.S. and the issues still to be confronted, including legal, societal -- and physical. It would seem that an illness like sickle cell disease should be conquered by now.
After all, it has been a known terror of the African-American community for more than 100 years. Perhaps, finally, genetic testing normally used during fertility treatment, and procedures that treat infertility, offer hope against the disease.
Studying Sickle Cell Anemia
Scientists have been studying sickle cell anemia for decades. I recently came across a biography of Dr. Roland Scott, a medical pioneer who researched and advocated for patients with sickle cell disease. Dr. Scott was born in Houston in 1909 and lived long enough to see Congress pass the Sickle Cell Anemia Control Act of 1971, which designated federal dollars to research and treat the disease.
As reported by journalist Renetta DuBose, Dr. Scott opened the Howard University Center for Sickle Cell Disease the next year and served as its director until 1990. He continued teaching at Howard as the premiere authority on the illness until his death in 2002 at the age of 93.
James Speer, a Licensed Certified Genetic Counselor at RMA of Connecticut, helped me understand what sickle cell anemia does and how it can be prevented. (A genetic counselor gathers detailed health and family histories, identifies conditions with genetic components and risk factors, discusses inheritance patterns, and provides information regarding genetic testing options.)
While parents with sickle cell traits are no more likely to be infertile than the rest of the population – about one in six couples have fertility issues – they can use procedures developed to treat infertility to have healthy babies. The latest techniques rely on new genetic tests in combination with in vitro fertilization (IVF).
“Sickle cell disease is a relatively common genetic disorder, with around one in 10 African-Americans carrying the sickle cell trait,” Speer said.
A person can carry a gene for the disease and be healthy. But if both parents have a copy of the gene, there is a 25% chance that their child will have sickle cell anemia.”
Those are lousy odds for a disease that causes symptoms like pain and shortness of breath even as it shortens lifespans. Today, couples who carry the sickle cell trait can pursue different options, Speer said, and avoid passing the disease to their children.
For them, they can try IVF combined with a technique called preimplantation genetic testing.
How IVF and Genetic Testing Can Help Prevent Sickle Cell Anemia
In vitro fertilization involves gathering eggs from the woman and inseminating them with sperm from her partner to create embryos. In preparation, genetic samples from both members of the couple as well as other family members are used to track the chromosome carrying the sickle cell mutation.
Preimplantation Genetic Testing can be used to find several different types of genetic issues, and couples screening for sickle cell disease can opt for all of them.
PGT for Monogenic Disorders (PGT-M) is used to detect the specific chromosome for sickle cell anemia in the embryo.
Additional genetic tests are often performed at the same time. PGT-A identifies aneuploidy, the term used to describe any embryo with either too many or too few chromosomes.
One form of aneuploidy causes Down syndrome, and other chromosomal maladies may cause up to 60 percent of miscarriages or prevent pregnancy altogether.
PGT-SR finds chromosome structural rearrangements, an inherited trait that results in extra or missing genetic material and often causes miscarriage.
“The results of all these tests will show which embryos have chromosome issues, including sickle cell.” Speer said. “The couple and their doctor could then decide which embryo to transfer.”
We are learning more every year about how genetics guide the inner workings of our bodies, and we can apply that knowledge to bring babies into the world without fear that they will suffer from certain life-altering diseases.
I knew a young woman who died of sickle cell anemia. Along with the shock and sadness, I thought about her grieving parents. I was sure they took comfort in their daughter’s intelligence and the career success she achieved in her too-short life, but I imagined their pain must have been nearly unbearable.
They would never trade the life they had with their daughter, but today I wonder whether they might take advantage of new methods to avoid the scourge of sickle cell disease.