[Nuclear quality of the spermatozoon: exploration tests of the chromatin of human spermatozoa (nuclear proteins)].

During spermiogenesis replacement of histones by protamines results in a highly condensed chromatin. Normal chromatin condensation is important for the function of the spermatozoa to carry the paternal genome. Abnormal chromatin can produce DNA damage such as denaturation or fragmentation and can be associated with impaired spermatogenesis. The degree of chromatin condensation can be studied with aid of different techniques: acidic aniline blue staining, chromomycin A3, acridine orange staining and sperm chromatin structure assay (SCSA), chromatin decondensation tests, gel electrophoresis of basic nuclear proteins em leader These tests provided valuable baseline information about semen or sperm preparation. If chromatin condensation is affected not only in malformed but also in morphologically normal spermatozoa, the proportion of spermatozoa with abnormal chromatin structure, in semen, appears to be potentially useful as predictor of fertilizing ability or pregnancy outcome.