Corporate Banner
Satellite Banner
Molecular & Clinical Diagnostics
Scientific Community
Become a Member | Sign in
Home>News>This Article

NIH Researchers Conduct First Genomic Survey of Human Skin Fungal Diversity

Published: Thursday, May 23, 2013
Last Updated: Thursday, May 23, 2013
Bookmark and Share
Location on the body surface determines fungal composition with the greatest diversity on feet.

While humans have harnessed the power of yeast to ferment bread and beer, the function of yeast or other types of fungi that live in and on the human body is not well understood. In the first study of human fungal skin diversity, National Institutes of Health researchers sequenced the DNA of fungi at skin sites of healthy adults to define the normal populations across the skin and to provide a framework for investigating fungal skin conditions.

Human skin surfaces are complex ecosystems for microorganisms, including fungi, bacteria and viruses, which are known collectively as the skin microbiome. Although fungal infections of the skin affect about 29 million people in the United States, fungi can be slow and hard to grow in laboratories, complicating diagnosis and treatment of even the most common fungal skin conditions, such as toenail infections.

The research team from the National Human Genome Research Institute (NHGRI) and the National Cancer Institute (NCI), both parts of NIH, extended their recent genome sequencing study of skin bacteria, using DNA sequencing techniques optimized for identifying fungi. The study appears in the May 22, 2013 early online issue of Nature.

The researchers found that a single type of fungus, belonging to the genus Malassezia, is predominant on the head and trunk. Hands, which harbor a great diversity of bacteria, are home for relatively few types of fungi. In contrast, feet, including toenails, heels and toe webs contain tremendous diversity.

“Applying DNA sequencing to a study of the skin’s fungi is the natural progression in understanding microbial life that co-exists on our bodies,” said NHGRI Scientific Director Daniel Kastner, M.D., Ph.D. “Along with recent genome sequencing to define bacterial diversity, this analysis of fungal diversity provides a more complete human microbiome picture.”

“Fungal communities occupy complex niches, even on the human body,” said Heidi Kong, M.D., co-senior author and an investigator in the dermatology branch of NCI’s Center for Cancer Research. “By gaining a more complete awareness of the fungal and bacterial ecosystems, we can better address associated skin diseases, including skin conditions which can be related to cancer treatments.”

The researchers collected samples at 14 body sites from 10 healthy adults. DNA sequencing of the fungi in the samples identified fragments of DNA, called phylogenetic markers, which can be counted and used to distinguish one type of fungus from another. The sequencing efforts generated more than 5 million markers, from the samples, representing more than 80 fungal types, or genera. In contrast, traditional culturing methods produced 130 colonies of fungi that represented only 18 fungal genera.

In 20 percent of the study participants, the researchers observed problems such as heel and toe web scaling or toenail changes consistent with possible fungal infections. From genome sequencing analysis, the researchers found that different individuals with heel site infections have common fungal communities at that site, while those with toenail infections display tremendously different fungal communities.

“DNA sequencing reveals the great diversity of fungi, even those that are hard to grow in culture,” said Julie Segre, Ph.D., co-senior author and senior investigator, NHGRI Genetics and Molecular Biology Branch. Her expertise is the development of microbial DNA sequencing technology. “DNA sequencing enabled us to learn immeasurably more about where fungi predominate as a part of the human skin microbiome.”

The researchers identified fungi from two phyla, Ascomycetes and Basidiomycetes, as part of the normal fungal census at the 14 skin sites. The most common genus Malassezia was present in 11 of 14 sites sampled on the body. The researchers found Malassezia fungus on every skin surface of healthy volunteers, whether on the back of the head, behind the ears, in nostrils and on the heels. Heels were also home to many additional fungi, including the genera Aspergillus, Cryptococcus, Rhodotorula, and Epicoccum.

“DNA sequence-based methods of identification enabled us to differentiate among species of fungi and to conclude that the diversity of fungi is highly dependent on the body site rather than the person who is sampled,” said Dr. Kong. A dermatologist, Dr. Kong explained why these sites were selected for exploration: “Our study focused on areas of the skin where we commonly find skin diseases that have been associated with fungi.”

The most complex site, the heel, is home to about 80 genus-level types of fungi. The researchers found about 60 types in toenail swab samples and 40 types in samples from the webs of the toes. Sites with moderate fungal diversity are inside the bend of the arm, inside of the forearm and palm, with each location supporting 18 to 32 genera of fungi. Surprisingly, head and trunk body sites — including the back, back of the neck, inside the ears, behind the ears, and between the eyebrows — have far fewer fungi types, with just two to 10 genera each.

The research team compared fungal diversity data with the skin bacteria on the same healthy adults. They found that while arms have high measures of bacterial diversity, they have lower fungal diversity. They found the reverse to be true for sites on the feet. Core body sites had neither a high bacterial diversity nor a high fungal diversity. The researchers had previously shown that bacterial diversity can be predicted by whether skin is moist, dry or oily. Fungal diversity, instead, seems to depend upon where a particular skin site is on the body.

The researchers observed, in addition, that there is greater similarity in the fungal community structure on the left and right sides of the same person’s body compared to the same body parts on any two individuals. Fungal communities also appear to be quite stable over time, with little change when tested on two separate occasions, up to three months apart.

“The data from our study gives us a baseline about normal individuals that we never had before,” Dr. Segre said. “The bottom line is your feet are teeming with fungal diversity, so wear your flip flops in locker rooms if you don’t want to mix your foot fungi with someone else’s fungi.”

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,600+ scientific posters on ePosters
  • More than 3,800+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Scientists Create World’s Largest Catalog of Human Genomic Variation
An international team of scientists from the 1000 Genomes Project Consortium has created the world’s largest catalog of genomic differences among humans, providing researchers with powerful clues to help them establish why some people are susceptible to various diseases.
Thursday, October 01, 2015
NIH Framework Points The Way Forward For Developing The President’s Precision Medicine Initiative
The NIH Advisory Committee to the Director has presented to NIH Director Francis S. Collins, M.D., Ph.D., a detailed design framework for building a national research participant group, called a cohort, of 1 million or more Americans to expand our knowledge and practice of precision medicine.
Monday, September 21, 2015
Undiagnosed Diseases Network Launches Online Application Portal
UDN Gateway enables patients to apply to national network of clinical sites.
Thursday, September 17, 2015
Using Genetic Sequencing to Manage Cancer in Children
A team of scientists have investigated the feasibility of incorporating clinical sequencing information into the care of young cancer patients.
Tuesday, September 15, 2015
Hastings Center Awarded NIH Grant
Funding has been awarded for a major project on goals and practices of next-generation prenatal testing.
Monday, September 14, 2015
NIH Grants Seek Best Ways To Combine Genomic Information and EHRs
Researchers seek to better understand genomic basis of disease, provide tailored care to patients.
Friday, September 04, 2015
Tumor DNA in Blood Reveals Lymphoma Progression
Using an advanced genetic test, researchers were able to detect diffuse large B-cell lymphoma (DLBCL) in blood serum before it could be seen on CT scans.
Tuesday, April 14, 2015
NIH Funds Nine Antimicrobial Resistance Diagnostics Projects
Investigators to develop tools to detect hospital-associated pathogens.
Friday, April 10, 2015
NIH Launches Tool to Advance Down Syndrome Research
Web portal will help approved professionals to plan clinical studies.
Wednesday, January 28, 2015
Sophisticated HIV Diagnostics Adapted For Remote Areas
New tool is low-cost, with no electricity needed.
Tuesday, December 02, 2014
NIH Names New Clinical Sites in Undiagnosed Diseases Network
Four-year, $43 million initiative engages broad expertise in study of mystery conditions.
Wednesday, July 02, 2014
Genetic Disorder Causing Strokes, Vascular Inflammation in Children Discovered
NIH researchers have identified gene variants that cause a rare syndrome of sporadic fevers, skin rashes and recurring strokes, beginning early in childhood.
Thursday, February 20, 2014
NIH, Industry and Non-Profits Join Forces to Speed Validation of Disease Targets
Goal is to develop new treatments earlier, beginning with Alzheimer's, type 2 diabetes, and autoimmune disorders.
Tuesday, February 11, 2014
Speeding Validation of Disease Targets
NIH, industry and non-profits join forces to develop new treatments earlier, beginning with Alzheimer’s, type 2 diabetes, and autoimmune disorders.
Tuesday, February 04, 2014
First Evidence-Based Diagnostic Criteria Published For TMD
The first evidence-based diagnostic criteria have been developed to help health professionals better diagnose temporomandibular disorders, commonly known as TMJ.
Monday, February 03, 2014
Scientific News
Detecting HIV Diagnostic Antibodies with DNA Nanomachines
New research may revolutionize the slow, cumbersome and expensive process of detecting the antibodies that can help with the diagnosis of infectious and auto-immune diseases such as rheumatoid arthritis and HIV.
Horse Illness Shares Signs of Human Disease
Horses with a rare nerve condition have similar signs of disease as people with conditions such as Alzheimer’s, a study has found.
Compound Doubles Up On Cancer Detection
Researchers have found that tagging a pair of markers found almost exclusively on a common brain cancer yields a cancer signal that is both more obvious and more specific to cancer.
The Age of Humans Controlling Microbes
Engineered bacteria could soon be used to detect environmental toxins, treat diseases, and sustainably produce chemicals and fuels.
Predictive Model for Breast Cancer Progression
Biomedical engineers have demonstrated a proof-of-principle technique that could give women and their oncologists more personalized information to help them choose options for treating breast cancer.
Are Changes to Current Colorectal Cancer Screening Guidelines Required?
Editorial suggests more research is needed to pinpoint age to end aggressive screening.
New Molecular Marker for Killer Cells
Cell marker enables prognosis about the course of infections.
Sniffing Out Cancer
Scientists have been exploring new ways to “smell” signs of cancer by analyzing what’s in patients’ breath.
New Test Detects All Viruses
A new test detects virtually any virus that infects people and animals, according to research at Washington University School of Medicine in St. Louis, where the technology was developed.
Scientists Create World’s Largest Catalog of Human Genomic Variation
An international team of scientists from the 1000 Genomes Project Consortium has created the world’s largest catalog of genomic differences among humans, providing researchers with powerful clues to help them establish why some people are susceptible to various diseases.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,600+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,800+ scientific videos