Ethnic diversity in precision medicine: a reality or an aspiration?

Precision medicine seeks to tailor prevention, diagnosis and treatment strategies to the biological and contextual characteristics of individuals. In diabetes, where there is substantial heterogeneity in risk, progression and treatment response, this approach holds particular promise. However, the majority of precision medicine research has been conducted in populations of White European ancestry, limiting its relevance and equity across ethnically diverse groups. This review examines the role of ethnicity in precision diabetes medicine, highlighting its potential value and limitations. It summarises evidence for ethnic variation in both type 1 and type 2 diabetes, including differences in susceptibility, phenotypes and complications, and demonstrates how under-representation in research has led to diagnostic and therapeutic blind spots. Three conceptual models for incorporating ethnicity into precision approaches are described: ancestry-anchored discovery, ethnicity-adapted translation and trait-based individualisation. Each model presents distinct opportunities for and challenges to equitable implementation. The review also outlines key barriers, such as limited diversity in discovery science, inconsistent data infrastructure, and resource constraints, and proposes practical strategies to overcome them. It concludes by identifying critical research gaps and emphasises the need for inclusive and context-sensitive models of precision medicine that account for both inter- and intra-ethnic diversity. Realising this vision will be essential to delivering effective and equitable diabetes care globally.