ObjectiveTo knock-in an EGFP cassette into the -globin genes of K562 cells via CRISPR/Cas9, and to assess expression and hydroxyurea (HU)-mediated induction of the targeted EGFP transgene.ResultsThe EGFP cassettes were specifically knocked into the G gene. EGFP expression was detected in the targeted cell population and isolated clones. Furthermore, EGFP transcript and fluorescence levels were significantly induced following HU-treatment.ConclusionThis system is readily utilizable for genome scale studies of cis-acting regulatory elements which are implicated in -globin expression or HU-mediated induction.