Abnormal morphology of germ cells in two infertile men

An abnormal morphology of germ cells has been found in two men with severely reduced fertility. Generally, in addition to Sertoli cells, only one cell type was present in the seminiferous tubules. Cells of this type differed considerably from normal spermatogonia. The diameter of the nuclei was considerably increased and they stained intensely with Feulgen stain. Spermatocytes and spermatids were absent in the abnormal tubules. Few, apparently normal, tubules were also present, which accounts for the finding of a small number of spermatozoa in the semen specimens. Both urinary excretion of gonadotrophins and 17-ketosteroids as well as secondary sex characteristics and chromosome complements were normal.