Novel assay for determining DNA organization in human spermatozoa: Implications for male factor infertility

Objectives. To present a novel assay for determining DNA organization in fertile human spermatozoa and establish morphometric parameters for these samples. The three-dimensional organization of DNA within a cell nucleus is intimately related to cellular function. For example, it has recently been demonstrated that normal sperm DNA organization may be necessary for successful in vitro fertilization in the mouse. Methods. Semen from 12 fertile volunteers was tested for sperm DNA organization using our nuclear matrix stability assay. Sperm DNA then underwent computerized digital image analysis and standards of normal were established. Results. Sperm DNA organization was constant in all samples tested. Normal parameters established included mean nuclear matrix diameter (9.17 +/- 1.59 mum), mean DNA halo diameter (20.56 +/- 2.53 mum), mean halo area (66.88 +/- 7.92 mum(2)), and mean nuclear matrix area (32.98 +/- 4.3 mum(2)). Conclusions. This assay may be used to determine DNA organization in a semen sample. Defining sperm DNA organization may be important clinically, because normal DNA organization is necessary for normal cellular function.