73

The cutaneous virome, defined as the collection of viruses detected in the skin, constitutes a significant part of the microbiota. A more recent discovery than bacterial flora, the existence of the cutaneous virome was unveiled through recent metagenomic studies. The virome of normal human skin is dominated by bacteriophages, Papillomaviridae—whose genomic diversity has proven extraordinary—and Polyomaviridae. Many viral genomes within this virome remain unidentified. The composition of the cutaneous virome has been shown to be strictly individual and relatively stable over time, reflecting its close adaptation to an individual’s genetics, lifestyle, and finely evolved mechanisms of immunological tolerance. Still underexplored, the cutaneous virome and its interactions with other microbiota microorganisms and with the host are attracting growing interest. Indeed, constitutional or acquired alterations in the homeostasis between the commensal virome and the skin, ranging from sub-clinical viral dysbiosis to severe transformation of keratinocytes or adnexal cells, have been observed. These recent findings are driving the search for innovative solutions to measure or even modulate its pathological expression, with promising prospects for personalized medicine.