Dec 2, 2022 - Research

A Check-In on 23andMe’s Sarcoidosis Research Study

Not too long ago, 23andMe launched a new study of sarcoidosis, specifically aimed at better understanding the underlying genetic and environmental factors that contribute to sarcoidosis in individuals with African ancestry. 

Sarcoidosis (pronounced SAR-COY-DOE-SIS) is a rare inflammatory disease affects the Black community at double the rate of white individuals, and can affect any organ, but most often, it occurs in the lungs. A study published in 2015 indicated that African-Americans were twelve times more likely to die from the condition than patients of other ethnicities. 

Participants in our Representation in Sarcoidosis Research Study have already begun sharing their own experiences with the disease. As people have consented to participate in our study, we are learning in real-time more about their earliest symptoms, the types of symptoms, and the treatments they’re using.

Our goal with this study is to gain new insight into the condition leading to potential new treatments or cures. That’s the hope as we work to recruit 2,000 individuals diagnosed with sarcoidosis with African ancestry.

New data

There is much we do not understand about sarcoidosis. It’s an insidious disease that can progress slowly without any obvious symptoms. It affects people of any age or ethnicity, but it’s usually diagnosed in adults between the ages of 30 and 40. It disproportionately affects people of African ancestry and is also more common in women.

While we still have a long way to go in our efforts, we’re already learning more about the condition. 

For example, among individuals participating in 23andMe’s study, we see that the most commonly reported symptoms were granulomas in the lungs or lymph nodes. Granulomas are tiny nodules where immune cells clump together at the site of an infection or inflammation. Almost 60 percent of those in the study reported granulomas on their lungs. About half said they had them on their lymph nodes. Other common symptoms of sarcoidosis are swollen lymph nodes, rashes, blurred vision, and joint pain or swelling.

23andMe’s early data shows a slightly higher prevalence among women participating in our study. It also shows a higher incidence among African Americans throughout our database. However, the latter may have more to do with our recruitment efforts.

Other symptoms

The data we have now is from both participants in the study and from customers who previously consented to participate in research. This preliminary data shows that lung scarring, also known as pulmonary fibrosis, is more prevalent among African Americans. The data we have so far also indicates that about a third (33 percent) of African Americans with sarcoidosis reported having lung scarring. This is compared to about 29 percent of all participants.  

You can get sarcoidosis at any age. But the risk increases as you get older, especially after age 55. The average age of diagnosis among our study participants is 41, but four years younger among African Americans in the study.

Common symptoms for sarcoidosis are fatigue, pain, and swelling. When the condition affects the lungs, symptoms often include persistent coughs and shortness of breath. When it affects the heart, the symptoms often result in an irregular heartbeat or swelling of the heart, known as edema. There currently is no cure and few approved treatments.

We’re learning how our data parallels what we generally know about sarcoidosis’s earliest symptoms and progression. But we’re also interested in the potential of how this data might offer new insights into the condition. We’re encouraged by how those insights might push us closer to finding new treatments for the disease.

Rare disease research

This study is among a host of studies 23andMe has recently undertaken, looking specifically at rare diseases. Rare disease is defined as conditions that affect fewer than 200,000 people in the US. It is often difficult to find and recruit enough people with the condition, and this is especially the case among the underrepresented population.

However 23andMe’s research model is uniquely suited to studying rare diseases. And in the months since launching the Representation in Sarcoidosis Research Study, we’re already seeing the power of our research model to quickly recruit individuals. This is in part because participation isn’t dependent on geography. People can participate in 23andMe research from home.

Just as with most other rare diseases, there is a strong genetic component to sarcoidosis. But many genetic variants associated with the condition have not yet been identified. 

Learn more about 23andMe’s sarcoidosis study here. Questions about the study? Contact us at

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