Research suggests human microbiome studies should include a wider diversity of populations

May 11, 2014

Microbial samples taken from populations living in the U.S. and Tanzania reveal that the microbiome of the human hand is more varied than previously thought, according to new research published in the journal Microbiology. These findings suggest that the 'standard' hand microbiome varies depending on location and lifestyle.

Results compared the microbes on the hands of women in the U.S. and Tanzania and found that organisms that have commonly been identified in prior skin microbiome studies were highly abundant on U.S. hands, while the most abundant bacterial species on Tanzanian hands were associated with the environment, particularly soil.

The team of researchers from Yale University, Stanford University and Johns Hopkins University Bloomberg School of Public Health, took hand wash samples from 15 adult American women and 29 adult Tanzanian women to compare the species of microorganisms present. In the U.S. group, all participants were graduate students, 13 of white European origin, while two were Chinese-American. In the Tanzanian group, all women were caregivers to children under 5 years of age, living in a low-income urban environment.

Dr Jordan Peccia from Yale University, who led the work, said: "If we ever hope to understand how the microbiome affects health and how environmental interactions alter it, we have to expand research to cover different populations.

"The microbial population on the graduate students' hands looks like what we think the hand microbiome 'should look like', but we can't assume that the human microbiome is a standard thing. Our research has shown that the on the things people use to interact with the environment the most – their hands – is dramatically different between groups."

The predominant microbial groups found on the US hands included members of the Propionibacteriaceae, Staphylococcaceae and Streptococcacease groups of bacteria, similar to those previously found in hand microbiome studies. In contrast, the Tanzanian samples included members of the Rhodobacteraceae and Nocardiodaceae not previously thought to be common colonisers of human skin. These groups are commonly associated with soil and aquatic environments.

The lifestyle differences between the groups are notable. None of the U.S. group was a caregiver for young children and the group spent the majority of their time indoors. The Tanzanian live in open-air dwellings in Dar es Salaam, Tanzania, and spend large amounts of time outdoors.

These results help to expand human results beyond U.S. and European populations, demonstrating the important role that the environment plays in shaping the microbes on people's hands.

Explore further: Report answers questions about the human microbiome and its role in health, obesity

More information: 'Hand Bacterial Communities Vary Across Two Different Human Populations' published online ahead of print in Microbiology.

add to favorites email to friend print save as pdf

Related Stories

Your body's microbiome has a unique 'fingerprint'

Apr 23, 2013

The microbiome is your body's set of microbial communities; microbial cells outnumber human cells roughly ten to one. Through studying the microbiome, scientists are learning more the relationship between these microbes and ...

Lifestyle determines gut microbes

Apr 15, 2014

An international team of researchers has for the first time deciphered the intestinal bacteria of present-day hunter-gatherers.

Recommended for you

Sugar mimics guide stem cells toward neural fate

13 hours ago

Embryonic stem cells can develop into a multitude of cells types. Researchers would like to understand how to channel that development into the specific types of mature cells that make up the organs and other structures of ...

Researchers uncover secrets of internal cell fine-tuning

Jul 29, 2014

New research from scientists at the University of Kent has shown for the first time how the structures inside cells are regulated – a breakthrough that could have a major impact on cancer therapy development.

User comments : 0