(Via EurekAlert). The tools of modern biotechnology are becoming ever more capable, as illustrated by this narrow view into telomere research: "Cancer researchers have long sought a way to subdue telomerase, an enzyme whose excessive activity contributes to the unchecked growth of as many as 90 percent of human tumors. ... In most healthy adult cells, telomerase is shut off, and telomeres slowly shrink during cell division - a normal process that helps limit cells' lifespan. Cancer cells, however, usually find a way to turn telomerase back on, achieving a dangerous immortality. ... We now have a detailed picture of the part of telomerase that forms this anchor site, and in fact have identified a groove within the protein that is what is really holding on to the end of the chromosome ... A molecule that would sit in that groove - even though it's far away from the active site - looks like it would completely abolish the ability of telomerase to work."