In the male reproductive system transforming growth factor‑β superfamily members including bone morphogenetic proteins (BMPs) and their receptors have been shown to regulate steroid production and male germ cell development vital for fertility. Many studies however have restricted their research to normal or cancerous cell lines derived from testicular cells, however data derived has not correlated well to results published from mice testis tissues and/or testicular cells directly. Therefore, in this study we clarify the expression patterns of BMPs in the testis directly to achieve a greater understanding of these vital genes and gain insight into their probable functions.

To determine the relative expression patterns of Bmp2, Bmp3, Bmp3b, Bmp4, Bmp5, Bmp6, Bmp7, Bmp8a, Bmp8b and Bmp15 in mouse testis across development we obtained fresh tissues at 2, 4, 6 and 8 weeks and performed total ribonucleic acid (RNA) extractions, RNA quantification followed by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Real time gene amplification results were analysed using beta-actin as the control.

All BMPs screened were expressed in the postnatal mouse testis at all developmental stages. With the exception of Bmp5 all genes screened were expressed at a higher level at 2 weeks then during adulthood. Bmp5 expression was least at 2 weeks and only increased its expression by 6 weeks of age. Bmp3 and Bmp15 were the lowest expressed genes while Bmp4, Bmp5, Bmp6, Bmp7, Bmp8a and Bmp8b were expressed in greater amount throughout development. Patterns of gene expression illustrated provide useful clues as to which BMP genes have predominance at particular developmental stages of germ cell development.