Across Species Identification of Genes Bridging Cognition and Reproduction

Evolutionary success in mammals requires coordinated regulation of cognitive functions and reproductive capacity. Such coordination must involve shared genes and molecular pathways between the brain and germ cells, yet direct evidence linking cognition to reproduction across species remains limited. Here, proteomic and transcriptomic analyses were performed experimentally in Ovis aries and Rattus norvegicus, while transcriptomic datasets from Mus musculus, Macaca mulatta, and Homo sapiens were analyzed in silico. We identified 8,464 protein-coding genes shared between the brain and sperm/testis and conserved across five species. In rats, 8,444 of these genes were also shared between the brain and the ovary. Functional annotation classified 3,890 genes as associated with both neurological and reproductive functions, and 1,752 as uncharacterized in these contexts, highlighting candidates for future studies on reproductive and neurological disorders. These findings reveal a deeply conserved genetic network linking neurological and reproductive systems, underscoring the evolutionary interplay that supports mammalian fitness.