The article focuses on a research conducted by researcher Lei Qi and colleagues related to reverse transcription and clustered, regularly interspaced, short palindromic repeats (CRISPR) system. According to the research, Cas9 endonuclease allows targeted RNA silencing. It also mentions that CRISPR system is effective for silencing endogenous genes of the lac operon, an operon required for the transport and metabolism of lactose in Escherichia coli.