A difference in dry mass between the heads of X- and Y-bearing human spermatozoa

Abstract

An integrating microinterferometer was used to measure the dry mass of sperm heads. The dry mass was proportional to DNA content and provided a useful method of estimating sperm DNA content. Using this technique, human spermatozoa which showed none and 1 quinacrine-fluorescent spot were found to be X- and Y-bearing, respectively. The measurements suggested that many of the spermatozoa with 2 quinacrine-fluorescent spots were not YY-bearing, as previously thought, but might be incompletely condensed Y-bearing spermatozoa.