- Round spermatids show normal testis-specific H1t but reduced cAMP-responsive element modulator and transition protein 1 expression in men with round-spermatid maturation arrest. Steger, K., Klonisch, T., Gavenis, K., Behr, R., Schaller, V., Drabent, B., Doenecke, D., Nieschlag, E., Bergmann, M., Weinbauer, G.F. J. Androl. (1999)