Stripes help chemists shop for molecules.

Scientists may soon be sticking bar-coded metal rods into molecules to see what they do in a crowd 1 . The rods could help to track the functions and interactions of genes, and may aid drug discovery.

At only a few thousandths of a millimetre long, the rods are small enough to fit inside a single red blood cell. Christine Keating, of Pennsylvania State University, and colleagues cast them inside cylindrical pores in a

A new way to find genes and map disease.

A new technique should aid the hunt for genes in the human genome sequence. The method, which tracks only switched-on genes in cells, will help researchers to distinguish between diseased and normal tissues, and could point the way to new treatments.

Andrew Simpson, of the Ludwig Institute for Cancer Research in Sao Paulo, Brazil, and colleagues have produced a whopping 700,000 DNA tags, representing the genes that are active in 24 no

Spells and incantations step aside: scientists have found a genetic elixir of love. It makes males more faithful to females and more friendly to fellow males. It could also shed light on bonding disorders such as autism.

Larry Young of Emory University in Georgia and colleagues used a virus to deliver a gene straight to the part of voles’ brains responsible for rewards and addiction, the ventral pallidum. The gene made the animals’ brains more receptive to the hormone vasopressin 1

Museum exhibits’ genes record British forestry policies

Commercial forest planting in the north of England drew red squirrels westwards in the 1980s say UK researchers. This migration led to big changes in squirrel numbers and genetics.

The finding has implications for the protection of the endangered red squirrel (Sciurus vulgaris). Many conservationists advocate leaving ’wildlife corridors’ for animals to travel between patches of fragmenting habitat. This is the first evi

Mouse studies emphasize children’s cancer risk from sunburn.

Serious sunburn in childhood may raise the risk of developing the deadliest form of skin cancer as an adult, research in mice suggests 1 . The experiments could lead to a better understanding of malignant melanoma and of how and when to protect ourselves from the sun.

“I have my kids wear hats and put sunscreen on like crazy now,” says the study’s leader Glenn Merlino, of the National Cancer Institu

Fossils bridge gap between land mammals and whales.

Fifty million years ago, two mammals roamed the desert landscapes of what is now Pakistan. They looked a bit like dogs. They were, in fact, land-living, four-legged whales.

Their new-found fossils join other famous missing links, such as the primitive bird Archaeopteryx , that show how one group of animals evolved into another. And they undermine the two prevailing theories about which land mammals are most closely re