Having the Trait – the Root of Sickle Cell

Posted on May 11th, 2024

Sickle Cell Is an Inherited Genetic Condition

Having sickle cell trait doesn’t mean that you have sickle cell disease. To have sickle cell disease, a person must inherit two sickle cell genes, one from each parent. A person who inherits the sickle cell gene from only one parent is called a trait carrier. A trait carrier is healthy but can pass the sickle gene to their children. Some people who carry the sickle cell trait don’t even know they have it. Most people with sickle cell trait will not have any symptoms or complications.

However, there are a few, rare health problems that may be related to sickle cell trait. One example is pain when traveling at high altitudes or engaging in strenuous exercise. Trait carriers or people living with sickle cell should speak with their doctor before starting an exercise program. 

Inheriting the Genes for Sickle Cell Disease and Sickle Cell Trait

In the image below, each parent has one normal hemoglobin gene and one sickle cell hemoglobin gene. This means each of their children has:

• A 25% chance of inheriting two normal hemoglobin genes, and not having sickle cell trait or disease

• A 50% chance of inheriting one normal hemoglobin gene and one sickle cell hemoglobin gene, and carrying the sickle cell trait

• A 25% chance of inheriting two sickle cell hemoglobin genes, and having sickle cell disease

Each time this couple has a child, the chances of that child having sickle cell disease remain the same. In other words, if their first child is born with sickle cell disease, there is still a 25% chance that their second child will also have sickle cell disease.