A TI{CRIMIC.TG4.1} DNA cassette has been inserted into Cyp4ac2, in a coding intron, and is predicted to gene trap all annotated transcripts of the gene. The insertion is also within tkv and is not predicted to gene trap this gene. The TI{CRIMIC.TG4.1} cassette was inserted via the CRISPR/Cas-9 drop-in technique, using a dsDNA donor vector with homology arms of length 200bp. The sgRNA sequence used to target the gene was: ATACATATGTATTTCAAAGCTGG.