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What is Sickle Cell?
Sickle cell is a progressive and unpredictable genetic disorder that affects red blood cells. Learn more about what causes this rare condition. 
Genetic disease a disease that is caused by a change, or mutation, in someone’s DNA sequence
Hemoglobin a protein in red blood cells that helps carry oxygen throughout the body

Sickle cell is a progressive and unpredictable genetic disorder that affects red blood cells. Learn more about what causes this genetic condition.

What Causes Sickle Cell?
Sickle cell is a progressive and unpredictable genetic disease caused by a change (mutation) in both copies of the HBB gene  that you inherit from your parents. This change affects the hemoglobin protein, which causes people with sickle cell to produce an abnormal form of hemoglobin called hemoglobin Sickle (HbS).  There are hundreds of variations in the HBB gene that can affect the hemoglobin protein. Although HbS is the most common abnormal form of hemoglobin, there are other variations. Because of this, there are different types of sickle cell.

Sickle cell is a progressive and unpredictable Genetic diseasea disease that is caused by a change, or mutation, in someone’s DNA sequence caused by a change (mutation) in both copies of the HBB gene that you inherit from your parents. This change affects the Hemoglobina protein in red blood cells that helps carry oxygen throughout the body, which causes people with sickle cell to produce an abnormal form of hemoglobin called hemoglobin Sickle (HbS). There are hundreds of variations in the HBB gene that can affect the hemoglobin protein. Although HbS is the most common abnormal form of hemoglobin, there are other variations. Because of this, there are different types of sickle cell.

In sickle cell, HbS proteins clump together, causing red blood cells to become sickle shaped, sticky, rigid, and fragile. You can think of red blood cells as a water balloon: healthy red blood cells are flexible and can flatten and squish through even the smallest of blood vessels. Sickled red blood cells, however, have a harder, less flexible consistency—like a water balloon full of ice chips instead of water—causing them to break apart, damage vessels, slow and/or stick and block blood flow throughout the vessels of the body. This leads to the symptoms and complications associated with sickle cell. 
Image of normal red blood cell and sickled red blood cell

Who Gets Sickle Cell?
Sickle cell affects millions of people throughout the world across a wide range of ethnicities. And although in the United States it is often perceived as a disease that only affects the Black community, it affects people of all races.

Sickle cell affects millions of people throughout the world across a wide range of ethnicities. And although sickle cell is often perceived as a disease that only affects the Black community, it affects people of all races. 
“Sickle cell is a blood disease and it can affect people of any ethnic background... The reality is that anyone can get this disease, and it can impact you or your family, and you might not care until it matters.”

— Rae, Parent

Prevalence of Sickle Cell

Estimates for the prevalence of sickle cell in the United States rely on consistent and complete reporting by universal newborn screening information. Although newborn screening has expanded in the past decade, differences in how information is collected varies by state, including how race and ethnicity are classified. These inconsistencies make it difficult to accurately estimate sickle cell prevalence information across the entire United States.

Although it is classified as a rare condition, as of 2023 the Centers for Disease Control and Prevention (CDC) estimates that sickle cell impacts ~100,000 Americans. Of these:

  ~1 of 365   Black births  

  ~1 of 16,300   Hispanic American births  

  ~1 of 25,800   Asian/Pacific Islander births*  

  ~1 of 41,600   non-Hispanic White births*  

  Affects men and women equally  

*Based on births in New York State between 2000 and 2008.

Sickle Cell Trait

According to a study published in 2014 by the CDC, as many as 60,000 children in the United States were born with the sickle cell trait. In 2010, based on newborn screening information provided by 13 states, the sickle cell trait was found in:

  ~73 per 1,000   Black infants  

  ~3 per 1,000   White infants  

  ~2 per 1,000   Asian, Native Hawaiian, or other Pacific Islander infants  

  ~7 per 1,000   Hispanic infants  

Although it is classified as a rare condition, as of 2023 it is estimated that sickle cell impacts ~100,000 Americans. Of these:

~1 of 365

Black births

~1 of 16,300

Hispanic American
births

~1 of 25,800

Asian/Pacific Islander
births*

~1 of 41,600

non-Hispanic White
births*

Affects men and
women equally

*Based on births in New York State between 2000 and 2008.

Sickle Cell Trait

According to a study published in 2014 by the CDC, as many as 60,000 children in the United States were born with the sickle cell trait. In 2010, based on newborn screening information provided by 13 states, the sickle cell trait was found in:

~73 per 1,000

Black infants

~3 per 1,000

White infants

~2 per 1,000

Asian, Native Hawaiian, or
other Pacific Islander infants

~7 per 1,000

Hispanic infants

 

What Can You Do?

Starting a conversation with your community about the prevalence of sickle cell can be a great first step in sparking change and gaining awareness. You can continue to dig deeper by learning how to be more proactive in the management of sickle cell.

Every voice, no matter how big or small, can spark a conversation and action to help drive change for sickle cell. Sign up to stay connected through email with resources, support, ways to connect with others, and more information about sickle cell.

Recognizing how sickle cell impacts your life may help spark important discussions with others to bring changes in your care and the care of your loved ones. How does sickle cell affect you?