Sickle Cell Disease - a Product of Gene Mutation

Sickle cell disease (SCD) is the most commonly inherited blood disorder experienced by Americans'"an estimated 70,000 to 80,000 live with the disease. Worldwide, millions are afflicted.

The Painful Reality

The term "sickle cell disease" applies to a family of inherited blood disorders. Onset usually occurs during early childhood. These disorders originate in mutations of the gene that codes for the protein hemoglobin. Hemoglobin enables red blood cells to absorb and transport oxygen throughout the body.

The red blood cells of sufferers are sickle-shaped rather than disc-shaped. These sickled cells die at a faster-than-normal rate, resulting in a low blood count (anemia). Pain usually accompanies an episode and is due to blood vessel blockage.

Since the body's tissues need oxygen to function, a reduction in red blood cells can lead to organ damage. The spleen may be affected, making the sufferer more vulnerable to infection. Additional symptoms can include jaundice and delayed growth leading to a delay in reaching puberty.

Severity of symptoms varies considerably. Proffered treatment for sickle cell disease involves treating symptoms and complications, and includes antibiotics, painkillers and blood transfusion.

Statistics of Sickle Cell Disease

Sickle cell disease displays an autosomal recessive inheritance pattern. This means that a sufferer would have had to receive a mutated gene from each parent. If both parents are carriers (they have one mutated gene and one normal gene each), their children will have a --

25 percent risk of inheriting sickle cell disease
25 percent of having no disorder
50 percent chance of being a carrier

Carriers have the "sickle cell trait," but are generally healthy.

American singer and actress, Tionne "T-Boz' Watkins suffers from Sickle Cell Disease.

Genetic Cause

The US National Library of Medicine says sickle cell results from mutations in the HBB (hemoglobin beta) gene'"the gene responsible for the production of beta-globin. Since the gene can mutate in a number of ways, there are a number of varieties of the condition. Says What is Sickle Cell Disease'"an article on the Sickle Cell Disease Association of America website'"the most common varieties are, "Sickle Cell Anemia, Sickle-Hemoglobin C Disease, Sickle Beta-Plus Thalassemia and Sickle Beta-Zero Thalassemia."

SCD Testing

A blood test can determine whether or not a person has sickle cell disease. Prenatal testing is also available, and in some of the United States newborn testing is standard procedure. Those within the U.S. who are concerned about the genetic disorder'"most sufferers are African Americans or Hispanics'" may seek genetic counseling.

Due to the considerable interest in sickle cell disease research, new treatments will doubtless be forthcoming.

References and Resources

Sickle Cell Disease Association of America: About Sickle Cell Disease

National Institutes of Health: What is Sickle Cell Anemia?

Centers for Disease Control: Sickle Cell Trait