Diving into the Genetics of Sickle Cell Disease
1/10/2019, 1:53 p.m.
The “Ask Dr. Kevin” series is brought to you by Pfizer Rare Disease in collaboration with the National Newspaper Publishers Association (NNPA) to increase understanding of sickle cell disease. Dr. Kevin Williams is the Chief Medical Officer for Rare Disease at Pfizer. He pursued medicine after being inspired by his father’s work as a general practitioner in his hometown of Baton Rouge, Louisiana. Dr. Kevin is passionate about raising awareness and increasing understanding of rare diseases, such as sickle cell disease, in the African American community.
In recent years, genetics has become a hot topic in popular culture, frequently making news headlines and serving as a key theme in movies and TV shows—and for good reason: our genes are what make us unique.
Genes not only help to shape our tastes and preferences, but they also can influence our health. In some cases, our genes play silent roles within our bodies. In others, genes take on a more prominent role, even determining our likelihood of having specific diseases.
This brings me to sickle cell disease (SCD), a topic I am passionate about and have discussed in previous articles. In this article, I’d like to focus on the often under-recognized fact that SCD is a genetic disease and is inherited from the passing of the sickle cell gene from parent to child.
Not everyone who inherits the sickle cell gene has SCD. Only people who inherit the gene from both parents develop this condition. This is an important distinction, as a person who inherits the sickle cell gene from only one parent while inheriting a normal gene from the other will have sickle cell trait, and typically will live a relatively normal life. However, people with sickle cell trait have a 50% chance of passing the gene to their children.
I’m here to answer some of the most common questions that I’m asked about the sickle cell trait and suggest available resources for additional information.
How prevalent is the sickle cell trait?
Research indicates that as many as 3 million Americans carry the sickle cell trait, primarily impacting African Americans. In fact, nearly 1 in 12 African Americans have the sickle cell trait.1
Worldwide, more than 100 million people carry the sickle cell trait. It is most prevalent among sub-Saharan Africans, Hispanics, South Asians, Caucasians from southern Europe, and people from the Middle East.1
Are there complications with having the sickle cell trait?
The majority of people who carry the sickle cell trait do not experience complications. However, that is not to say that everyone with the trait remains symptom-free. Though rare, extreme conditions such as severe dehydration, high-intensity physical activity, and low oxygen environments (e.g.: high-altitude locations) can lead to serious health issues or even sudden death for individuals with the sickle cell trait.1
How do you know if you have the sickle cell trait?
All it takes is a simple blood test to learn if you have the sickle cell trait. You can talk with your doctor or a health clinic about getting the test.