At the crossroads of chromosomes

PHILADELPHIA — On average, one hundred billion cells in the human body divide over the course of a day. Most of the time the body gets it right but sometimes, problems in cell replication can lead to abnormalities in chromosomes resulting in m…

Scientists find two forms of genetic material chromatin

Biologists have discovered what appear to be fundamental differences in the physical properties of the genetic material known as chromatin. Chromatin packages DNA into cells, and the scientists found the differences between chromatin that packages genes and the chromatin that packages DNA with regulatory or unknown functions. The variation represents a previously unrecognized level of genomic organization and complexity, the scientists report, one that may exist in all cells with nuclei.

Oral drug turns on silenced genes, turns off cancer

Oral administration of a drug that inhibits a process known as DNA methylation results in a reduction in the size of malignant tumors in mice, according to a team of researchers led by scientists from the Keck School of Medicine of the University of Southern California. The drug, called zebularine, accomplishes its tumor-whittling by turning on tumor suppressor genes that have been turned off by methylation.