The Transcriptomics and Epigenomics of Hair Follicles

Hair follicles (HF) are the only mammalian organ with the ability to regenerate cyclically throughout adult life. To do so, a highly heterogeneous community of cell subpopulations work together driving proliferation, lineage specification, and differentiation. Identifying and characterizing this diversity has been a research interest for the past decades and now, advances in sequencing with single-cell resolution are now helping elucidate the complexity underlying HF biology. Herein, we briefly describe the functional anatomy of HFs and the major cell subpopulations that have been identified through conventional methods. We also discuss the technologies used to elucidate the transcriptomic profiles of HFs, focusing on single-cell resolution. Furthermore, we describe prominent studies that have recently been published with the aim of understanding HF heterogeneity. We also introduce the use of sequencing technologies for querying epigenetic modifications and spatial transcriptomics. Additionally, we discuss the origin and the use of exosomes for hair regeneration.