Distinguishing the testes-specific genes in different species may disclose key genes associated with testes-specific functions and provide sufficient information for the study and treatment of male infertility. A testes‑specific gene, coiled-coil domain containing 38 (Ccdc38), was identified by screening UniGene libraries. Systematic bioinformatics analysis demonstrated that the CCDC38 protein was conserved in various mammalian species. It was determined that CCDC38 was exclusively expressed in testes and its expression increased from 2‑8 weeks of age. Additional immunohistochemical analysis indicated that CCDC38 was mainly expressed in spermatogonia and spermatocytes. It is of note that, immunofluorescence and co-immunoprecipitation assays demonstrated that CCDC38 interacted with ubiquitinated histone H2A in mouse testes. Therefore, these results suggest that Ccdc38 is a testes-specific gene, which may be important for mouse spermatogenesis.