An improved method for Y-body identification and confirmation of a high incidence of YY sperm nuclei.

The fluorescence of Y-bodies and brightly fluorescing autosomal heterochromatin in quinacrine mustard stained interphase nuclei treated with distamycin A is more brilliant than in nuclei stained only with quinacrine and mustard. In the present study examinations with the aid of this method in several probands and different tissues are described. The effect of distamycin A is demonstrated to depend on its dose and the time of exposure to it. An exceptionally high frequency of YY sperm nuclei, previously also described by other studies, is confirmed in the present work. A hypothesis explaining the effect of distamycin A in interphase nuclei is discussed.