News

  1. Eggs and more grown from mouse stem cells

    Stem cells from mouse embryos can be converted into eggs, skin, or heart muscle.

    By John Travis
  2. Earth

    Vermiculite turns toxic

    Federal agencies issued a warning that much of the vermiculite ceiling insulation installed a decade or more ago may be tainted with cancer-causing asbestos.

    By Janet Raloff
  3. Earth

    To contain gene-altered crops, nip them in the seed

    Researchers have demonstrated that, in principle, they can add genes that block genetically modified crops from breeding with conventional varieties and thus from spreading their artificial traits.

    By Ben Harder
  4. Math

    Uncovering a prime failure

    Mathematicians have returned to the drawing board after what looked like a dramatic step forward in understanding prime numbers.