Genomic medicine that uses a programmable RNA sensor and switch to selectively enable expression of a nucleic acid payload in specific cell types, namely, programmable RNA molecules used for sensing, detecting, modifying, and targeting certain cell types to deliver DNA and RNA therapeutics; Modular RNA molecules programmed to one or more transcript expression profiles to target certain cell types for the delivery of therapeutics; Programmable RNA-sensing technology that detects, monitors, and targets cells to treat various diseases.