Experimental Models and Molecular Pathogenesis: An Integrated Review of Alopecia

A disconnect between mechanistic discovery and the physiological relevance of preclinical models fundamentally hampers the development of effective therapies for alopecia. This review critically bridges the pathogenic underpinnings of major hair loss disorders—androgenetic alopecia, alopecia areata, telogen effluvium, and chemotherapy‐induced anagen effluvium—with a focused evaluation of the experimental models designed to study them. We analyze how established platforms, from transgenic mice to xenografts, have elucidated key pathways involving androgen signaling, immune privilege collapse, and follicular cytotoxicity. More importantly, we interrogate the limitations of these models in replicating the chronicity and complexity of human disease, a gap that persists despite significant mechanistic insights. We conclude that the field requires a paradigm shift toward integrated, human‐relevant systems—such as immune‐competent organoids and engineered tissue platforms. This synthesis not only maps the current experimental landscape but also provides a framework for developing next‐generation models to accelerate translational research.