Total RNA was isolated using Trizol (Invitrogen #15596026, per the manufacturer's protocol) from triplicate samples of 3-4 kidney organoids for each of CRISPR, AAV, and Control samples on differentiation day 28, following 7 days of treatment with AAV2-saCas9 + AAV2-gRNA, AAV2-GFP, or vehicle control, respectively. RNA was quantified (Thermo Scientific Nanodrop One spectrophotometer) and its integrity assessed (RNA Nano 6000 Assay Kit, Bioanalyzer 2100, Agilent Technologies, CA). cDNA was synthesized from 500 ng of RNA using a High-capacity cDNA Reverse Transcription kit (Applied Biosystems).