A bad case of underestimating the amount of work to set up a CRISPR screen in flies.
The last time I tried CRISPR mutagenesis I got 17 adult flies from one injection and 23 from another. 40 single crosses in total and only 50% were fertile. Which meant the 4 batches of PCR screening per founder line wasn't too traumatic (until the point I discovered there weren't any mutants).
This time I decided to increase the number of injections and different mutant designs. I figured 6 injections wouldn't be too much of an extra workload based on previous runs. I mean it would probably result in 6 x 30 crosses so less than 200. Perfectly manageable. Well, I currently have 300 crosses set up and at least another 100 to set up.
If I think that's painful just wait until I reach the stage where I have to collect virgins from 400 separate crosses. Here's hoping some of them are sterile and that there's a mutant in there somewhere!
Even more fun is the fact I have another 2 injections arriving tomorrow.
A little bit of staggering or crosses at different temperatures may be required.