The function and the relevance of a gene on the pathogenesis of disease can be readily studied with great precision by removing (gene knockout), modifying (gene mutation), and overexpression (transgenesis) of genes in laboratory animals, mouse in particular. IRCM transgenic core facility, SPF-microinjection, is located in two animal facilities CPA and SPF+, offering services including DNA and RNA (crispr/cas9) microinjection into fertilized egg pronuclear, gene targeting in pluripotent embryonic stem (ES) cells, ES cell blastocyst microinjection, decontaminating mouse line (rederivation) and mouse line rescuing, conservation and management of genetically modified mouse lines. Recently new genomic editing technology (Crispr/cas9) has been very successfully adapted at IRCM. With this technology, it is easier to target a gene.