The article reviews the biology and genomics of human hair follicles, focusing on androgenetic alopecia (AGA). AGA is a common condition affecting men, with genetic and hormonal factors playing key roles. The study discusses the functional anatomy of hair follicles (HFs), including their four main regions: bulb, suprabulb, isthmus, and infundibulum. The HF is a complex organ capable of regeneration, regulated by a "hair clock" involving epithelial-mesenchymal interactions. The study highlights the role of stem cells in hair regrowth and the importance of the dermal papilla (DP) in regulating hair cycling. The hair cycle consists of three phases: anagen (active growth), catagen (apoptotic involution), and telogen (resting). AGA is characterized by the miniaturization and atrophy of hair follicles, associated with dysregulation of the hair cycle. Androgens, particularly dihydrotestosterone (DHT), play a central role in AGA, interacting with androgen receptors (ARs) in the DP. Genetic predisposition, along with environmental and lifestyle factors, contributes to AGA. The study also discusses the molecular mechanisms underlying AGA, including signaling pathways such as WNT/β-catenin and BMP, and the role of inflammation in the pathogenesis of AGA. Transcriptional studies have identified differentially expressed genes (DEGs) in AGA-affected and non-affected regions, with genes related to inflammation, androgen signaling, and fibrosis being overrepresented. Genome-wide association studies (GWAS) have identified several genetic variants associated with AGA, including those in the AR and EDA2R loci. These findings highlight the complex genetic and molecular basis of AGA. The article also reviews current treatments for AGA, including finasteride and minoxidil, and discusses emerging therapeutic strategies targeting signaling pathways involved in hair regeneration. The study emphasizes the need for a multi-omics approach to better understand the complex mechanisms of AGA and develop more effective treatments. Overall, the review underscores the importance of understanding the molecular and genetic basis of AGA to improve treatment outcomes.The article reviews the biology and genomics of human hair follicles, focusing on androgenetic alopecia (AGA). AGA is a common condition affecting men, with genetic and hormonal factors playing key roles. The study discusses the functional anatomy of hair follicles (HFs), including their four main regions: bulb, suprabulb, isthmus, and infundibulum. The HF is a complex organ capable of regeneration, regulated by a "hair clock" involving epithelial-mesenchymal interactions. The study highlights the role of stem cells in hair regrowth and the importance of the dermal papilla (DP) in regulating hair cycling. The hair cycle consists of three phases: anagen (active growth), catagen (apoptotic involution), and telogen (resting). AGA is characterized by the miniaturization and atrophy of hair follicles, associated with dysregulation of the hair cycle. Androgens, particularly dihydrotestosterone (DHT), play a central role in AGA, interacting with androgen receptors (ARs) in the DP. Genetic predisposition, along with environmental and lifestyle factors, contributes to AGA. The study also discusses the molecular mechanisms underlying AGA, including signaling pathways such as WNT/β-catenin and BMP, and the role of inflammation in the pathogenesis of AGA. Transcriptional studies have identified differentially expressed genes (DEGs) in AGA-affected and non-affected regions, with genes related to inflammation, androgen signaling, and fibrosis being overrepresented. Genome-wide association studies (GWAS) have identified several genetic variants associated with AGA, including those in the AR and EDA2R loci. These findings highlight the complex genetic and molecular basis of AGA. The article also reviews current treatments for AGA, including finasteride and minoxidil, and discusses emerging therapeutic strategies targeting signaling pathways involved in hair regeneration. The study emphasizes the need for a multi-omics approach to better understand the complex mechanisms of AGA and develop more effective treatments. Overall, the review underscores the importance of understanding the molecular and genetic basis of AGA to improve treatment outcomes.