The Arsenic Bug - Busted!

Last year, the scientific world was briefly rocked by the assertion that a bacterium that lived in Mono Lake could incorporate arsenic in place of phosphate in its DNA.  Rather rapidly, however, doubts began to creep in, as people actually read the details, and began to see holes in the rationale and methods.  Now, new doubts surface, as scientists fail to duplicate the results:

Study Fails to Confirm Existence of Arsenic-Based Life

A strange bacterium found in California’s Mono Lake cannot replace the phosphorus in its DNA with arsenic, according to researchers who have been trying to reproduce the results of a controversial report published in Science in 2010.

A group of scientists, led by microbiologist Rosie Redfield at the University of British Columbia in Vancouver, Canada, have posted data on Redfield's blog that, she says, present a “clear refutation” of key findings from the paper.

“Their most striking claim was that arsenic had been incorporated into the backbone of DNA, and what we can say is that there is no arsenic in the DNA at all,” says Redfield.

This is supposed to be how science actually works.  A finding should be repeatable, and a hypothesis need to survive further tests. In reality, lots of findings are never tested again, often because they were trivial LPUs (least publishable units) to begin with, and their importance was such that no one had any wish to spend hard earned research funds attempting to replicate them.