Word: chromatin
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...little dark spot that others lack. Yet not until 1949 did Canadian Neuro-Anatomist Murray L. Barr realize that the spots, which he was studying in cats' nerve cells, appear only in cells from females. Later research showed that the spots, now known as "Barr bodies" or sex chromatin, consisted of one X chromosome - the one that is inactivated after it has done its job of helping to determine femaleness...
...method is based on the fact, demonstrated by Canadian scientists (TIME, Feb. 23, 1953), that a substance called sex chromatin can be detected in female but not in male cells. Dr. David Serr and Geneticists Leo Sachs and Mathilde Danon of Jerusalem's Rothschild-Hadassah University Hospital reasoned that cells in the amniotic fluid, the liquid inside the sac that encloses the fetus, could be analyzed to reveal the child's sex. To get small samples of the fluid, they inserted an extremely fine hypodermic needle through the vagina and into...
...Canadian believes that he has solved the diagnostic problem in human intersex. All human cells, says Dr. Murray L. Barr of the University of Western Ontario, contain something called sex chromatin. It is easy to spot in females' cells, because there it is made from two husky X chromosomes. It is not seen in male cells, because they draw on only one X chromosome and a measly little Y chromosome...
Harvey reasoned that since female-producing sperm seems to contain slightly more chromatin (chromosome material), it must be slightly heavier. The problem, therefore, is to separate "biological isotopes." Harvey, citing a centrifuge method which has separated the light and heavy parts of sea urchins' eggs, thinks it can be done. His proposal: use a special centrifuge to whirl the sperm; the lighter male-producing sperm will rise to the top, can be skimmed off and planted by artificial insemination...
Under the supervision of Dr. Stanley Cobb, Dr. F. Fremont Smith and Dr. Hans Zinsser of Harvard's Department of Neuropathology, Dr. Morrison killed five dogs suffering from running fits, made histological brain examination. He found the nuclei of the brain cells broken into bits, with chromatin scattered throughout the cell body. He discovered also great clusters of spider and mossy cells of the neuroglia around the small blood vessels in the white matter of the brain. In normal tissue, these supporting cells should be distributed in rows throughout the white matter. Cell peculiarities of the type found...