A project launched several years ago in New York City is making its way to cities around the world—much like the bacteria that the world's billions of transit users transfer around the surfaces of subway trains, stations, and buses.

The Centre for Genomic Regulation put out a press release earlier this month announcing the latest developments in the MetaSUB research project: an unprecedented study of urban mass-transit systems and cities around the world with the goal of creating to establish a "DNA map" of the microbiomes found in mass transit systems.
According to the press release, "[m]ass transit systems represent unique urban biomes, microbiomes, and metagenomes," enabled by "perhaps one of the world’s largest, high-traffic, and universal built environments."
The release notes the invisible importance of the microbiome in the biological makeup of humans ("bacterial cells in and on our bodies outnumber human cells by a 10:1 ratio," for instance). According to the release, "[t]he data produced by the consortium will benefit city planners, public health officials, and designers, as well as the discovery of new species, biological systems, and biosynthetic gene clusters (BGCs), thus enabling an era of more quantified, responsive, and 'smarter cities.'"
June 21 was the "Global City Sampling Day" for the MetaSUB project. Barcelona is the latest large city to join the project, which began in 2013 in New York City. The New York City effort already produced a widely circulated microbiome map of that city's subway system.
FULL STORY: MAPPING THE SUBWAY’S MICROBIOME

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