Navel Gazing Just Got More Interesting

Researchers in the Belly Button Biodiversity project released the first round of DNA results from their analysis of 95 human navel swabs, reports The Washington Post's Peter Aldhous. So far, the analysis has revealed more than 1,400 bacterial strains — in 662 cases, Aldhous says, the microbes couldn't be classified, leading the research team's leader, North Carolina State University's Jiri Hulcr, to say that these microbes are "new to science." The project was first thought up as a semi-joke, but the new discoveries are making an important contribution to the understanding of microbial diversity, Aldhous adds. Identifying the bacterial species is the next step, but could prove difficult. A team at the University of Colorado at Boulder has classified the microbes into "operational taxonomic units," with 16S ribosomal RNA gene sequences that differ by 3 percent or less. "Apply this standard to mammals, Hulcr explains, and dogs and cats would be lumped together," Aldhous says. "It means that a 'match' between a belly button strain and a species known from the deep ocean, for instance, may actually represent two microbes separated by several million years of divergent evolution." While the researchers have recorded a large number of strains so far, he adds, the results indicate that about 40 species account for about 80 percent of the belly button bacterial populations.