Genetic Factors May Delay Diabetes Diagnosis in Black and Asian Men

Recent research highlights a significant yet often overlooked genetic factor that can impede timely diagnosis of type 2 diabetes among Black and South Asian men in the UK, with potential implications worldwide. A study conducted by the University of Exeter in partnership with Queen Mary University of London identified that approximately one in seven Black men and one in 63 South Asian men carry a genetic variant known as G6PD deficiency. This condition, though typically asymptomatic, can interfere with common blood tests used to diagnose diabetes.

G6PD deficiency does not directly cause diabetes but has a critical impact on the accuracy of the HbA1c blood test, the globally accepted method for diagnosing and monitoring diabetes. The HbA1c test measures average blood sugar levels over time, but in individuals with G6PD deficiency, results tend to be artificially low, leading healthcare providers to potentially miss or delay a diabetes diagnosis.

Patients with G6PD deficiency are diagnosed with diabetes approximately four years later than those without the gene variant, increasing their risk for serious complications such as nerve damage, kidney issues, and vision problems. The study, published in Diabetes Care under the title "Undiagnosed G6PD deficiency in Black and Asian individuals is prevalent and contributes to health inequalities in type 2 diabetes diagnosis and complications," emphasizes that current screening practices are insufficient, especially in populations where G6PD deficiency is common.

Experts like Professor Inês Barroso from the University of Exeter stress the importance of revising testing protocols to include routine G6PD screening, particularly for at-risk populations. Recognizing and addressing this hidden genetic risk could significantly reduce health disparities and improve early diagnosis rates.

G6PD deficiency affects over 400 million people worldwide, predominantly among those with African, Asian, Middle Eastern, and Mediterranean heritage. Its prevalence among Black and South Asian men in the UK underscores the urgent need for tailored diagnostic approaches. Without early identification, individuals with G6PD deficiency face a 37% higher risk of developing microvascular complications associated with diabetes.

Healthcare professionals and policymakers are called to action to increase awareness and incorporate genetic screening into standard practices. Dr. Veline L'Esperance from Queen Mary University of London highlights that better screening can prevent delays and improve health outcomes for communities disproportionately affected by diabetes.

The study analyzed genetic data from over half a million participants through the UK Biobank and Genes & Health projects, revealing that current reliance on HbA1c testing may contribute to underdiagnosis in certain ethnic groups. As researchers advocate for further studies in diverse populations, the goal remains to create equitable diagnostic strategies that eliminate these health inequalities. source: https://medicalxpress.com/news/2025-09-hidden-genetic-delay-diabetes-diagnosis.html