The insertion of Velocigene cassette ZEN-Ub1 created a deletion of size 2623bp between positions 4889494-4892116 of Chromosome 19 (Build GRCm39). The single exon was replaced by a LacZ reporter cassette followed by a neomycin resistance cassette. Western blot analysis confirmed the absence of protein expression in the testis and cauda epididymal sperm from homozygous mutant mice.