In the pageant of life, we are genetically bloated. The human genome contains around 20,000 protein-coding genes. Many other species get by with a lot less. The gut microbe Escherichia coli, for example, has just 4,100 genes.

Scientists have long wondered how much further life can be stripped down and still remain alive. Is there a genetic essence of life? The answer seems to be that the true essence of life is not some handful of genes, but coexistence.

E. coli has fewer genes than we do, in part because it has a lot fewer things to do. It doesn’t have to build a brain or a stomach, for example. But E. coli is a versatile organism in its own right, with genes allowing it to feed on many different kinds of sugar, as well as to withstand stresses like starvation and heat.

Continue reading “How Simple Can Life Get? It’s Complicated” →

If you are still waiting for Swarmageddon to break out in your backyard, it is time to stop. The great cicada invasion is winding down for 2013, and it will not be back for another 17 years.

After dwelling in the ground since 1996, the insects began to emerge in May from North Carolina to the Hudson River Valley. In yards, forests and fields up and down the coast, they trilled by the billions, mated, laid their eggs in branches and left exoskeletons on bushes and walkways. Now their song is fading.

But while many people were kept up at night by the roar of this arthropod flash mob, others were left to wonder what all the fuss was about.

Continue reading “Swan Song for Cicadas, but Many Missed the Show” →

Bert Vogelstein, a cancer geneticist at Johns Hopkins University, says he is haunted by three pictures.

The first shows a man’s upper body studded with large melanomas. The second shows what happened when the man took a drug called vemurafenib. Vemurafenib belongs to a relatively new class of drugs, called targeted cancer therapy. Unlike earlier chemotherapy drugs, they attack specific molecules found only in cancer cells. In response to the vemurafenib, the tumors shrank in a matter of weeks, to the point that the man’s skin looked smooth and healthy.

Continue reading “Studying Tumors Differently, in Hopes of Outsmarting Them” →

The laboratory of Vera Gorbunova and Andrei Seluanov, a husband-and-wife team of biologists at the University of Rochester, has the feel of a petting zoo. They maintain colonies of several species of rodents — some familiar, like mice and guinea pigs, and some much more exotic, like blind mole rats from Israel and naked mole rats from East Africa.

Amusing children with furry creatures is not their goal, however. The biology of animals is mysteriously diverse, and lurking within it may be clues to new kinds of medicine.

Continue reading “A Homely Rodent May Hold Cancer-Fighting Clues” →