Update: DNA Transposition

Note: this entry contains minor spoilers about the solutions to the two DNA Transposition puzzles. Go solve them first!

Back when the first DNA Transposition puzzle was printed in Imagine, we were concerned that readers would not completely understand how to solve the puzzle given the abbreviated instructions printed in the available space. In situations like this, the website comes in handy: we can post detailed instructions and examples and print a link in the magazine in case readers want more information. So that’s what we did, but I never got around to posting the actual puzzle (or the second one) until now.

Regardless, I discovered and fixed a few flaws in the original graphics before posting this update. Most of my attention focused on the solution graphics, both the path through the apparatus and the tree diagram showing the problem space. Finding the appropriate way to show a path that loops and doubles back on itself in a single diagram was tricky. I found that creating template path pieces worked best – these could be assembled then merged together to form one seamless, semi-transparent path.

path pieces

Representing loops in the problem space diagrams presented a similar challenge. I first charted out each problem space on paper, then created a digital version that could be rearranged so that loop connections would be close together (or as close together as possible). Several alignment issues were also corrected in the problem space diagrams.

Compounding all of this in the second puzzle was, in addition to an intended (shortest) solution, an additional solution that merited attention. This meant creating multiple solution path graphics, all of which needed to share the same visual language, and creating a single problem space chart that could highlight each solution separately while still being compact and coherent overall.