July 31, 2020
Clinical Contributors to this Story
Alfred Gillio, M.D. contributes to topics such as Pediatric Hematology Oncology.
Stacey Rifkin Zenenberg, D.O. contributes to topics such as Pediatric Hematology Oncology.
Expectant parents often muse about which genetic traits their kids will inherit. Will their son have his father’s dimples? Will their daughter have her mother’s curly hair? Unfortunately, what they don’t always consider is that the genetic traits they pass along might also endow their baby with a gift no parent wants to give: chronic pain—and perhaps even a shorter lifespan.
That’s what’s at stake for individuals who carry a genetic mutation known as the sickle trait, which can become sickle cell disease in some children who inherit it.
Although it originated in Africa thousands of years ago, sickle cell disease wasn’t discovered until 1910 in the United States. That’s when a dental student from the island of Grenada visited a Chicago doctor’s office with symptoms of anemia and complaints of severe pain. The doctor gave the case to a resident, who examined the patient’s blood under a microscope and noticed red blood cells that were sickle-shaped instead of round.
Since then, much has been discovered about sickle cell disease. If the condition runs in your family, here are five of the most important facts you should know about it.
- You can carry the sickle trait even if you don’t have sickle cell disease.
Sickle cell disease is caused by an inherited mutation in the gene that’s responsible for making hemoglobin, the molecule in red blood cells that carries oxygen from the lungs to the rest of the body. Because the mutation is a recessive trait, it can exist in DNA without becoming sickle cell disease. In fact, it only manifests as sickle cell disease in people who inherit the mutation from both parents.
“If mom’s a carrier and dad’s a carrier, then their baby will be born with sickle cell disease,” says pediatric hematologist/oncologist Alfred Gillio, M.D., director of the Children’s Cancer Institute at the Joseph M. Sanzari Children’s Hospital at Hackensack University Medical Center.
- Sickle cell disease can occur in people of any ethnicity.
Although sickle cell disease is most prevalent in individuals of African descent, it’s also common in Spanish, Mediterranean, Pakistani and Indian populations, according to Stacey Rifkin Zenenberg, D.O., a pediatric hematologist-oncologist at Joseph M. Sanzari Children’s Hospital, where she is section chief for pediatric pain and palliative care. If the sickle cell trait exists in their gene pool, bi-racial and even Caucasian children also can develop it.
- Pain “crises” are sickle cell’s signature symptom.
Pain is the hallmark of sickle cell disease. “The genetic mutation that causes sickle cell disease changes the shape of red blood cells, which changes how they carry oxygen,” Dr. Rifkin Zenenberg explains. “The cells tend to stick together, which can cause occlusions, or blockages, in very small blood vessels. This can cause acute pain episodes that we call ‘crises’ in the organs and extremities—especially in certain circumstances, like when it’s cold outside or when the body is fighting an infection.”
- Sickle cell disease can cause organ damage, stroke and even death.
When organs are deprived of oxygen, pain is just one consequence. Another is organ damage—to the liver, heart, kidneys, gallbladder and eyes—and even stroke. Dr. Gillio says sickle cell patients also may suffer from acute chest syndrome, which resembles pneumonia, and splenic sequestration, which occurs when sickled blood cells get stuck in the spleen, causing a sudden drop in hemoglobin, painful splenic swelling and/or permanent scarring that damages the spleen’s ability to filter infections from the blood. All of this puts sickle cell patients at increased risk of premature death.
- There are potential cures for sickle cell disease.
While the most common treatment is hydroxyurea—a chemotherapy drug that helps reduce the number and frequency of pain crises in people with sickle cell disease—patients now also have at least two curative therapies available to them.
The first is bone marrow transplant, which replaces a patient’s unhealthy stem cells with healthy ones provided by a matching donor, which usually but not always is the patient’s sibling.
The second, which currently is undergoing clinical trials, is a gene therapy that allows patients to be their own donors. Doctors harvest stem cells from the patient, modify them in a laboratory by adding a corrected gene that makes non-sickle hemoglobin, administer chemotherapy that kills off the patient’s existing stem cells, then transfuse the patient with his or her own genetically modified stem cells. Thereafter, the patient can produce normal red blood cells that nullify the effects of sickled red blood cells.
“Transplant and gene therapy are curative therapies,” Dr. Gillio says. “We can now give kids who are born with sickle cell disease a normal life and a normal lifespan.”
Next Steps & Resources
- Meet our sources: Alfred Gillio, M.D. and Stacey Rifkin Zenenberg, D.O.
- To make an appointment with Drs. Gillio or Rifkin Zenenberg, or a doctor near you, call 800-822-8905 or visit our website.
- Learn about a gene therapy clinical trial for sickle cell currently underway at Joseph M. Sanzari Children’s Hospital: firstname.lastname@example.org or 551-996-5600
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The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.