Silence of the Xs.(X chromosome inactivation) Author/s: John Travis Issue: August 5, 2000 Does junk DNA help women muffle one X chromosome? Here's a riddle that will stump most people. What do calico cats--those popular felines with a patchwork of orange-red, black, and white fur--have in common with women who lack sweat glands on portions of their bodies? A clue: Calico cats are almost always female. The women and cats illustrate the remarkable fact that …showed first 75 words of 2356 total…

…showed last 75 words of 2356 total…bind to that RNA. Still, Eichler's latest work has given him a greater appreciation for the possibility that DNA sequences such as L1 elements have some role in human biology. "We as scientists have this preconceived notion, based on very little data, that this selfish DNA is nothing more than junk. I think junk is a very unfortunate term. It's more a reflection of our ignorance," he says. COPYRIGHT 2000 Science Service, Inc. COPYRIGHT 2000 Gale Group