Sickle cell trait skews common diabetes test
A genetic trait that affects red blood cells and is fairly common among African Americans and Hispanic Americans can cause an important blood sugar test to miss signs of diabetes, researchers say.
The test known as hemoglobin A1c (HbA1c) estimates long-term blood sugar levels by measuring the amount of glucose sticking to red blood cells, but blood cells from people with sickle cell trait don’t live as long, so they have less time to collect glucose.
When lead author Mary Elizabeth Lacy from Brown University School of Public Health in Providence, Rhode Island, and her colleagues used standard HbA1c cutoffs to screen for diabetes, “we identified 40 percent fewer cases of prediabetes and 48 percent fewer cases of diabetes in individuals with sickle cell trait than in those without sickle cell trait,” she told Reuters Health by email.
Sickle cell disease is a serious condition that occurs when a person has two copies of a defective gene responsible for making part of the hemoglobin molecule in red blood cells. Hemoglobin allows the cells to carry oxygen to the tissues that need it, but in people with two copies of the faulty gene, blood cells can turn sickle-shaped, causing painful crises and even death.
People with only one copy of the defective gene are said to have sickle cell trait, and most have no symptoms of sickle cell disease. The gene is most common among people with ancestry in sub-Saharan Africa, Central America and South America, Saudi Arabia, India, Turkey, Greece and Italy.
The U.S. Centers for Disease Control and Prevention estimates that 1 in 13 African American babies are born with sickle cell trait… Read More>>