Transposase evolved to insert DNA at specific locations

https://www.science.org/content/article/jumping-gene-enzyme-can-make-big-precise-changes-human-dna
An enzyme usually used by bacterial transposons to move from one place to another in the bacterial genome has been modified and evolved to insert large pieces of DNA into specific locations in mammalian genomes.   It uses the guide RNA of CRISPR to identify specific genomic sequence and they evolved the enzyme in order to improve the rate that it would insert sequence at the guide RNA location.  They used an in vivo selection environment where bacteria with the the enzyme had to survive viral infection.  They could survive viral infection if the enzyme could perform specific functions in the bacterial cell, so random mutations in the enzyme were selected for improved ability to perform the required duties.  They ended up with an enzyme that was much better than what they started with, and it could be useful for inserting large gene length segments of DNA into the human genome for fixing genetic defects.
Ron Okimoto