The insertion of a transgene containing a 4.1kb tyrosinase mini gene under the control of the tyrosinase promoter in line Bart97b produced a 11kb deletion spanning 6 exons (chr17:17,848,861-17,849,039 based on the GRCm38/mm10 assembly). RT-PCR confirmed complete absence of RNA transcripts in homozygous testis. (J:216863)