Gene editing has enabled us to push the limits of synthetic biology with multiple technologies such as CRISPR-Cas9, TALENs (transcription activator-like effector nucleases), and ZFNs (zinc-finger nucleases), which focus on cutting the DNA sequence at specific sites to edit it.

While these have been highly versatile and improvised for multiple applications, they are limited in scale. Using recombination and a retron library, scientists from the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard Medical School have designed a high-throughput gene editing method called Retron Library Recombineering (RLR).

RLR can edit millions of DNA sites simultaneously, where each mutation can be followed and screened with its unique barcode. This enables simultaneous and quantitative analysis of millions of experiments which can help understand the interplay of mutations at the whole genome level.