Always darkest ...

While idly scrolling through Facebook Monday morning, I encountered a number of links like this:

Study finds contamination in virus link to fatigue | Reuters

Scientists conclude mouse virus does not cause ME | Society |
The Guardian

Chronic Fatigue Syndrome is not caused by XMRV |
Wellcome Trust Blog

This looked bad. The headlines implied that some new discovery had invalidated all research linking ME/CFS (myalgic encephalomyelitis, aka "chronic fatigue syndrome") to a retrovirus. That contamination in the laboratory had skewed the results. Was it time to throw up our hands and look elsewhere for answers and possible treatments?

Eh. Not exactly. Despite the definitive tone of those headlines, and despite the researchers' bold claims, the latest studies only show that contamination is possible with a particular kind of test. They didn't refute the positive studies, which used four different methods of detection.

From Amy Dockser Marcus of the Wall Street Journal:

Robert A. Smith, a research assistant professor at University of Washington in Seattle who wrote a commentary in Retrovirology summarizing the studies ... said he is unwilling to state that the reported link between XMRV and CFS or prostate cancer is no longer viable.

The papers focus on various problems associated with a specific kind of test used to detect XMRV but does not examine every method used to detect XMRV. Smith pointed out that some of the previous papers on prostate cancer found XMRV integrated into the patients’ DNA and "I can’t come up with a mechanism where there would be contamination there.”

(Full story here.)

In other news, today marks the winter solstice—the shortest day of the year.

After today, bit by bit, the days grow longer and lighter.