C. David Allis

C. David Allis (1951-2024) formulated the histone code hypothesis, proposing that combinatorial patterns of histone post-translational modifications constitute a regulatory code read by effector proteins to control gene expression, fundamentally transforming our understanding of epigenetic regulation. He discovered that Gcn5 is a histone acetyltransferase, directly linking transcriptional coactivators to chromatin modification and establishing the paradigm of chromatin-modifying enzymes in gene regulation. His laboratory later identified recurrent histone H3 mutations (oncohistones) in pediatric brain tumors, demonstrating that histone mutations can directly drive cancer. His conceptual framework of writers, readers, and erasers of histone marks remains the organizing principle of chromatin biology.