Sickle cell anemia is a genetic blood disorder that affects the shape of red blood cells. These cells are shaped like crescent moons, or sickles, which can cause them to become stuck in small blood vessels and cause blockages. This can lead to a variety of symptoms, including pain, fatigue, and organ damage. In this blog, we will explore the concept of codominance and how it relates to sickle cell anemia.
What is Codominance?
Codominance is a genetic term that refers to a situation where both alleles of a gene are expressed in the phenotype of an organism. In other words, it is when both versions of a gene are present and active in an individual, rather than one version being dominant and the other being recessive.
How Does Codominance Apply to Sickle Cell Anemia?
Sickle cell anemia is caused by a mutation in the HBB gene, which provides instructions for making the beta-globin part of hemoglobin, a protein that carries oxygen in red blood cells. The mutation results in the production of an abnormal form of hemoglobin known as hemoglobin S.
In individuals with sickle cell anemia, the HBB gene has two copies, one normal copy and one copy with the sickle cell mutation. These two copies are codominant and both express the sickle cell trait. This means that the person inherits one copy of the gene from each parent. This results in the person having the disease.
In contrast, individuals who have only one copy of the HBB gene with the sickle cell mutation, have a condition called sickle cell trait. These individuals do not have the disease but they can pass the gene on to their offspring.
Conclusion
Sickle cell anemia is a genetic blood disorder caused by a mutation in the HBB gene. Codominance plays a key role in the inheritance of this disorder, as it is caused by the presence of two copies of the HBB gene with the sickle cell mutation. Understanding the genetics of sickle cell anemia is important for proper diagnosis and treatment of this inherited disorder. If you or a loved one is at risk for sickle cell anemia, it is important to speak with a healthcare professional to discuss genetic testing and counseling.