MiSeq DNA sequencing was performed by Macrogen, using the Illumina 300bpPE. To prepare the library, DNA was isolated from liver, heart, muscle and lung from mice transduced with sgRNA-control- or sgRNA-LCS2-encoding AAVs. Next, we amplified the target region of the Cas9 nuclease with the Pfu DNA polymerase (Promega) adding the Illumina adapters by two PCRs: NGS1_fwd: ACACTCTTTCCCTACACGACGCTCTTCCGATCTNNNNTGTGACACTGGAGGCAGAAG and NGS1_rev: GTGACTGGAGTTCAGACGTGTGCTCTTCCGATCTCAAGTCCCCATCACTTGGTT for the first PCR, and NGS2_fwd: AATGATACGGCGACCACCGAGATCTACACTCTTTCCCTACACGACGCTCTTCCGATCT and NGS2_rev: CAAGCAGAAGACGGCATACGAGATXXXXXXGTGACTGGAGTTC for the second PCR. The N represents random bases and the X the sequence used for the index. Genomic reads in FASTQ format were aligned to the GRCm38.p6 assembly of the mouse genome using BWA v. 0.7.5a-r40520 (link). Then, reads spanning the genomic region putatively affected by the CRISPR/Cas9 action (chr3: 88482555-88482615) were extracted with Samtools v. 1.3.121 (link) and analyzed using in-house Perl scripts. Briefly, these scripts isolate the part of each read spanning the chosen region, highlight small insertions/deletions and output a count of each regional sequence. Then, we analyzed the percentage of the sequences showing regional differences in sgRNA-control- and sgRNA-LCS2-transduced mouse samples.