design: To amplify the barcodes, we added 200 ng genomic DNA, 20 M of primer and each product from each condition was amplified with a unique i7 and i5 index, and Q5 high-fidelity DNA polymerase with the high-GC buffer, and standard Q5 reaction buffer (NEB). The cycle was as follows: 98C for 4 minutes, then cycled between 98C for 30 seconds, 61C for 30 seconds, 72C for 30 seconds, then followed by a final extension at 72C for 5 minutes. To purify the 196 bp desired product, two rounds of dual size selection with Sera-Mag Select (Cytiva) magnetic beads were used with 200 L of BarSeq PCR products.