Galvanic separation of X- and Y-bearing human spermatozoa

Separation of X- and Y-bearing human spermatozoa with the sephadex gel-filtration method

By means of the Sephadex gel filtration method we were able to separate a fraction rich in X-bearing human spermatozoa, in contrast with the method of Ericsson et al. (1973), which allows to obtain a fraction rich in Y-bearing sperm. The method, which is simple and not time-consuming, may allow control of sex in cases of expressed sex desire in off-spring.

Zeta potential of human X- and Y-bearing sperm

The zeta potential of human X- and Y-bearing sperm was measured by two different methods: (i) using an electrophoretic light scattering spectrophotometer, and (ii) using a laser-rotating prism. The X- and Y-bearing sperm were separated by free-flow electrophoresis, and their purities were determined by staining for the F-body using quinacrine mustard. The zeta potential of the sperm in the fraction containing more than 80% Y-bearing sperm was approximately -16 mV, whereas that of sperm in the fraction containing more than 95% X-bearing sperm was approximately -20 mV. In other words, the net negative-charge on the cell surface of human X-bearing sperm is higher than that of Y-bearing sperm.

Enrichment of human X- and Y-chromosome bearing spermatozoa by density gradient centrifugation

Human spermatozoa (120--180 Mill/0.6 ml Tyrode solution) were laid on the top of a continous density gradient column consisting of 4--16% bovine serum albumin. The columns were then centifuged at 1500--1600 rpm (200-240 g) at 20 degrees C or 4 degrees C for 15 min. By this procedure the spermatozoa sedimented within the tubes of normal distribution curves. The mean percentages of y-spermatozoa gradually decreased from 62,3 +/- 6,1% (max. 70%) in the upper fractions to 42,4 +/- 3,8% (min. 37%) in the bottom fractions. These results could be verified by inseminations of rabbit does with spermatozoa separated by the same technique.

Enrichment of X-spermatozoa and in vitro penetration through cervical mucus

Using the Sephadex Gel-filtration method (Steeno - 1975) we carried out a review of the data on the possibility of enriching X-spermatozoa. The testing procedure followed consisted of determining Y-chromatin positive spermatozoa after staining with quinacrine-mustard. We were able to confirm the data recorded by Steeno, according to which an enrichment of about 80-90% can be achieved after penetration through the Sephadex Gel filter. In addition to these investigations we also carried out tests with the enriched X-spermatozoa material to determine in vitro penetration through cervical mucus. No decline in the progressive motility of the spermatozoa was observed. After the Gel-filtration sufficient numbers of these were still able to cover penetration distances of 60 mm/hour. The enrichment effect of the X-spermatozoa declined at the beginning of in vitro penetration, but there was no further change in the subsequent course of penetration.