Researchers reported two technical advances aimed at improving adenine base editor (ABE) precision. A study published in Nature Biotechnology used directed evolution to alter enzyme properties and paired those editors with 3′-extended guide RNAs to narrow editing windows and cut bystander edits. The work demonstrates a clear, reproducible path to reduce unintended A→G conversions that complicate therapeutic use. The second paper introduced CHANGE-seq-BE, a genome‑wide assay tailored to profile off‑target activity of base editors with high sensitivity. CHANGE-seq-BE maps editing events across genomic DNA, enabling quantification of low-frequency bystander and off‑target edits that standard assays miss. Together, the studies pair engineering and measurement: one reduces unwanted edits, the other detects residual off‑target activity for safety assessment. Clarification: adenine base editors chemically convert adenine to guanine at target sites without double-strand breaks, but “bystander” edits occur when nearby adenines are unintentionally edited, a clinical safety concern.