CRISPR/Cas9 technology was used to delete exons 2-5 of the mouse Serpina3c gene by non-homologous recombination. qPCR analysis demonstrated that mRNA expression was abolished in multiple tissues, including brown adipose tissue (BAT), inguinal and epididymal white adipose tissue (WAT), liver, and muscle. Western blot analysis confirmed the absence of protein expression in the inguinal and epididymal WAT of homozygous mutant mice.