Washington, May 29 (Inditop): Human skin is home to a much wider array of bacteria than previously thought, a new study by National Institutes of Health researchers has shown.
The study has also shown that at least among healthy people, the greatest influence on bacterial diversity appears to be body location. For example, the bacteria under one person’s arms could be more similar to those under another person’s arm than they are to the bacteria that live on your forearm.
These variations in bacterial habitats may explain why some skin complaints tend to affect certain areas of the body.
“Our work has laid an essential foundation for researchers who are working to develop new and better strategies for treating and preventing skin diseases,” said Julia A. Segre, Ph.D., of the National Human Genome Research Institute (NHGRI), who was the study’s senior author.
“The data generated by our study are freely available to scientists around the world. We hope this will speed efforts to understand the complex genetic and environmental factors involved in eczema, psoriasis, acne, antibiotic-resistant infections and many other disorders affecting the skin,” Segre added.
Drawing on the power of modern DNA sequencing technology and computational analysis, the research team from NHGRI, the National Cancer Institute (NCI) and the NIH Clinical Center uncovered a far more diverse collection of microbes on human skin than had been detected by traditional methods that involved growing microbial samples in the laboratory.
The study involved taking skin samples from 20 sites on the bodies of 10 healthy volunteers.
Study co-author Maria L. Turner, M.D., senior clinician in NCI’s Dermatology Branch, said: “We selected skin sites predisposed to certain dermatological disorders in which microbes have long been thought to play a role in disease activity.”
The researchers extracted DNA from each sample and sequenced the 16S ribosomal RNA genes, which are a type of gene that is specific to bacteria.
The researchers identified more than 112,000 bacterial gene sequences, which they then classified and compared. The analysis detected bacteria belonging to 19 different phyla and 205 different genera, with diversity at the species level being much greater than expected.
To gauge how much the skin microbiome differs among healthy people, the researchers studied many different parameters.
They found considerable variation in the number of bacteria species at different sites, with the most diversity being seen on the forearm (44 species on average) and the least diversity behind the ear (19 species on average).
The study was published today in the journal Science.
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