Demonstration of X chromatin in drumstick-like nuclear appendages of leukocytes by in situ hybridization on blood smears.

An X chromosome specific nucleic acid probe was used to study the positions of the X chromosomes in leukocyte nuclei by in situ hybridization to smears of peripheral blood. This autoradiographic approach allowed the first direct demonstration of the presence of X chromosomal material in the drumstick-like structures of female polymorphonuclear leukocytes.