Deoxyribonucleic Acid Content of the Germinal Vesicle of the Ovocyte in Fasciola hepatica

Abstract

SINCE deoxyribonucleoproteins possibly constitute a substratum of the genome, the problem of the permanent character of deoxyribonucleic acid in the cell nucleus is of much present interest, and especially in the elements of the germinal lineage. However, it is known that in the nucleus of the primary ovocyte, after it swells to form a germinal vesicle, Feulgen's reaction becomes negative, or in some species very slightly positive. J. Brachet¹ demonstrated by means of centrifugation that, even in the cases of negative Feulgen's reactions, deoxyribonucleic acid is present in the germinal vesicle, but too dilute to give a visible re-coloration of the fuchsin: after centrifugation, a centrifugal cap of the acid was detected even in cases of negative reaction. The permanent character of the deoxyribonucleic acid was also qualitatively demonstrated in the germinal vesicle; but the quantitative aspect of the problem remains, so far as we know, still an open question.