Mapping human brain cell type origin and diseases through single-cell transcriptomics

The human brain, a pinnacle of biological complexity, comprises a diverse array of cell types that regulate cognition and maintain neural homeostasis. Advances in single-cell transcriptomics have revolutionized neuroscience by enabling high-resolution molecular profiling, revealing unprecedented insights into cellular heterogeneity, lineage dynamics, and disease-associated states. Large-scale brain-mapping initiatives have identified numerous novel cell types, yet their functional roles in health and disease remain poorly understood. This review synthesizes current knowledge of brain cell diversity, from neurogenesis to pathological states, and highlights key gene markers that define cellular identity and function. By integrating insights from single-cell transcriptomics, we explore how cellular diversity shapes brain function and contributes to disease mechanisms, providing a foundation for future research and translational applications.