Overview

• A PNAS study by researchers at the University of Pittsburgh, UPMC and Instituto Aggeu Magalhães demonstrates that genetic ancestry directly influences dengue severity through immune activity in skin explants.
• Skin samples with higher European ancestry showed amplified inflammatory responses that recruit myeloid cells into a ‘friendly fire’ loop, increasing viral spread.
• When cytokines were added to African-ancestry skin samples, the same infection-promoting inflammation emerged and blocking those signals sharply reduced dengue infection rates.
• The findings provide the first biological explanation for long-observed milder dengue cases in individuals of African descent compared to those of European ancestry.
• Scientists plan to map specific gene variants behind these ancestry-linked responses and apply the insight to tailored risk assessment, therapies and vaccine development.