Deletion of theGene Induces Sperm Alterations and In Vitro Hypofertility in Mice.

Abstract

Thanks to the analysis of an Interspecific Recombinant Congenic Strain (IRCS), we previously defined thequantitative trait locus as an interval on mouse Chromosome 1 associated with male hypofertility and ultrastructural abnormalities. We identified the Spermatogenesis associated protein 3 gene (or) as a pertinent candidate within thelocus and performed the CRISPR-Cas9 mediated complete deletion of the gene to investigate its function. Male mice deleted forwere normally fertile in vivo but exhibited a drastic reduction of efficiency in in vitro fertilization assays. Mobility parameters were normal but ultrastructural analyses revealed acrosome defects and an overabundance of lipids droplets in cytoplasmic remnants. The deletion of thegene reproduces therefore partially the phenotype of the hypofertile IRCS strain.