New Subtype of Diabetes Discovered in Sub-Saharan African Youths
Guest Contributor
A groundbreaking study has revealed a newly identified subtype of diabetes in young people from sub-Saharan Africa, challenging long-standing assumptions about how the disease presents in this population. While type 1 diabetes is typically characterized as an autoimmune disorder, researchers have found that the majority of youths diagnosed with the condition in this region do not show the usual markers—suggesting the existence of a novel, non-autoimmune form of diabetes. This discovery could have far-reaching implications for how the disease is diagnosed and treated across diverse populations.
In the largest study of its kind, researchers led by Jean Claude Njabou Katte at the University of Exeter examined 894 Black African youths from Uganda, Cameroon, and South Africa, all of whom had been diagnosed with type 1 diabetes and were receiving insulin therapy. The team tested for three key autoantibodies typically associated with the autoimmune form of the disease, as well as genetic markers that indicate increased risk for type 1 diabetes. What they found was striking: 65 percent of participants lacked both the autoantibodies and the genetic risk factors commonly linked to the condition.
This finding suggests that classical type 1 diabetes may not be the predominant form of the disease in sub-Saharan Africa. Instead, many of these young people appear to have a different subtype—one that does not originate from an autoimmune attack on insulin-producing beta cells. While these youths are still insulin-deficient, their condition may arise from alternative mechanisms that remain poorly understood. I found this detail striking, as it underscores how much we still have to learn about the global diversity of diabetes.
Autoimmune type 1 diabetes is typically diagnosed by the presence of autoantibodies that signal the immune system is attacking the pancreas. In high-income regions such as Europe and North America, these markers are found in the vast majority of cases. However, prior research had already hinted that autoantibodies are less frequently detected in sub-Saharan African populations. What makes this new study significant is its scale and rigor. By analyzing both immunological and genetic data, the researchers were able to provide a clearer picture of what distinguishes this new subtype from more familiar forms of the disease.
Among the 894 participants, only 35 percent had the classic profile of autoimmune type 1 diabetes: the presence of autoantibodies, extremely low insulin levels, and high genetic risk. The remaining 65 percent, while still insulin-deficient, had slightly higher insulin levels and a median genetic risk score that was 18 percent lower. They also did not display features typical of type 2 diabetes or malnutrition-related diabetes, further suggesting that they represent a distinct clinical category.
To better understand how this new form compares with diabetes in other populations, the team also reviewed data from over 3,000 participants in the U.S.-based SEARCH for Diabetes in Youth study. In that cohort, autoantibody-negative diabetes was observed in only 15 percent of Black American youths and 9 percent of white American youths. Interestingly, only the Black American group without autoantibodies showed similarly low genetic risk scores as the African group. This parallel hints at a potential genetic or environmental link between the two populations, though much more research is needed to confirm this.
Experts not involved in the study have weighed in on the significance of the findings. Silvana Obici of Stony Brook Medicine noted that the research highlights how the most common form of diabetes in sub-Saharan Africa may differ substantially from what's seen elsewhere. Dana Dabelea from the Colorado School of Public Health emphasized the importance of further study, pointing out that this new subtype might eventually require a different standard of care. For now, insulin remains the primary treatment, but understanding the root causes could lead to more targeted therapies in the future.
Several hypotheses have been proposed to explain the origins of this non-autoimmune subtype. One possibility is the presence of unknown genetic factors that make beta cells more vulnerable to damage. Another theory suggests that chronic infections, early-life malnutrition, or environmental toxins could play a role. Soumya Adhikari from Children’s Health in Texas also raised the idea that undiscovered autoantibodies might be involved, which current tests are unable to detect.
The implications of this research are profound. It challenges the assumption that type 1 diabetes presents the same way across all populations and underscores the need for more inclusive, globally representative studies. For clinicians working in sub-Saharan Africa and other underserved regions, recognizing that many patients may not fit the classical profile of type 1 diabetes is crucial for providing effective care. It also highlights the importance of developing diagnostic tools and treatment protocols that reflect the biological diversity of the disease.
As the global health community continues to grapple with the complexities of diabetes, this study serves as a reminder that one-size-fits-all approaches may overlook critical nuances. The discovery of a new diabetes subtype in sub-Saharan African youths opens the door to more personalized and equitable healthcare strategies—ones that take into account the full spectrum of human genetic and environmental diversity.
