Selective curbing of unwanted RNA editing (SECURE) DNA base editor variants

A method of deaminating a selected cytidine in a genomic DNA, the method comprising contacting the genomic DNA with a cytosine base editor comprising rat apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 1 (rAPOBEC1) of SEQ ID NO:67, bearing one or more mutations that decrease RNA editing activity while preserving DNA editing activity, wherein the mutations are R33A, K34A, or R33A+K34A (double mutant), relative to SEQ ID NO:67, and a programmable DNA binding domain.