The effects of circumcision on the penis microbiome.
BACKGROUND
Circumcision is associated with significant reductions in HIV, HSV-2 and HPV infections among men and significant reductions in bacterial vaginosis among their female partners.


RESULTS
We assessed the penile (coronal sulci) microbiota in 12 HIV-negative Ugandan men before and after circumcision. Microbiota were characterized using sequence-tagged 16S rRNA gene pyrosequencing targeting the V3-V4 hypervariable regions. Taxonomic classification was performed using the RDP Naïve Bayesian Classifier. Among the 42 unique bacterial families identified, Pseudomonadaceae and Oxalobactericeae were the most abundant irrespective of circumcision status. Circumcision was associated with a significant change in the overall microbiota (PerMANOVA p = 0.007) and with a significant decrease in putative anaerobic bacterial families (Wilcoxon Signed-Rank test p = 0.014). Specifically, two families-Clostridiales Family XI (p = 0.006) and Prevotellaceae (p = 0.006)-were uniquely abundant before circumcision. Within these families we identified a number of anaerobic genera previously associated with bacterial vaginosis including: Anaerococcus spp., Finegoldia spp., Peptoniphilus spp., and Prevotella spp.


CONCLUSIONS
The anoxic microenvironment of the subpreputial space may support pro-inflammatory anaerobes that can activate Langerhans cells to present HIV to CD4 cells in draining lymph nodes. Thus, the reduction in putative anaerobic bacteria after circumcision may play a role in protection from HIV and other sexually transmitted diseases.
Price
Lance B
LB
Translational Genomics Research Institute (TGen), Flagstaff, Arizona, United States of America. lprice@tgen.org
Liu
Cindy M
CM
Johnson
Kristine E
KE
Aziz
Maliha
M
Lau
Matthew K
MK
Bowers
Jolene
J
Ravel
Jacques
J
Keim
Paul S
PS
Serwadda
David
D
Wawer
Maria J
MJ
Gray
Ronald H
RH
D001421:Bacteria, Anaerobic / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D001499:Bayes Theorem; D002944:Circumcision, Male; D006801:Humans; D008297:Male; D010413:Penis / Q000382:microbiology*; D012329:RNA, Bacterial / Q000235:genetics*; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D013045:Species Specificity
D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S