Nature 212, 1593 (31 December 1966); doi:10.1038/2121593a0

Technique for Investigation of Sex Chromatin in Amniotic Membrane of Rat Foetuses

NÉSTOR O. BIANCHI & MARTHA S. A. DE BIANCHI

Comisión de Investigación Científica de la Provincia de Buenos Aires, La Plata, Argentina.

SEX chromatin in the amniotic cells of rat foetuses is useful for sex diagnosis before the development of the gonads, especially in view of the fact that sexual dimorphism is not conspicuous in other tissues^1,3. To be a simple and accurate technique, however, the preparation of amnion for the examination of sex chromatin requires some special precautions. Absolute or 95 per cent alcohol has been habitually used as the fixative³, but we feel that it is troublesome because it shrinks the cells and coagulates the mucopolysaccharides. Cells of rat foetuses have several heterochromatic bodies^1,3, and consequently sex chromatin is not easy to distinguish when the cells shrink. Furthermore, the amnion in young rat foetuses has a considerable content of mucopoly-saccharides which when coagulated hinder fixation and make the cells difficult to see. To overcome these difficulties we have used 50 per cent glacial acetic acid as the fixative, and have obtained with it good fixation and swelling of cells, which makes it easier to differentiate sex chromatin from chromocentres.

References

1.	Bianchi, N. O., and de Bianchi, M. S. A., Cell Res., 31, 236 (1963). | Article | ChemPort |
2.	Carr, D. H., and Walker, J. E., Stain Technol., 36, 233 (1961). | PubMed | ISI | ChemPort |
3.	Feiner, U., Acta Anat., 43, 1 (1960). | PubMed | ChemPort |