In human clinics, pathologies as diverse as cancer, sepsis, autoimmune diseases, among others; of different etiology and a different pathophysiological behavior, converge in a failure of gene repression that allows the phenotypic expression of the disease; The possibility of having a biological marker that shows these events to the clinician is desirable since it would allow early diagnostic and therapeutic strategies. Micro RNAs are small and non-coding RNAs that fulfill that “genetic silencing” role, however, the step from basic research to clinical applicability, that is, their translational utility is still little diffused in specialties other than oncology. The objective of this review is to explain in a more precise way.