Distribution of bacterial community structures on human scalp hair shaft in relation to scalp sites.

Bacterial community structure on the human skin is specific to each individual and varies among different body sites. In this study, we investigated differences in bacterial community structure among five hair sampling sites and among 12 individuals. Significant differences were found between individuals in terms of alpha diversity and relative abundance of major bacterial phyla and genera, whereas no differences were found between hair sampling sites. The principal coordinate analysis plots of within-individual group tended to converge individually, whereas those of within-hair sampling site group did not clustered. In addition, weighted UniFrac analysis showed that the individual-based category was a statistically significant category but not the scalp hair sampling site-based category. These results suggest that the distribution of bacterial community structures on scalp hair shafts within individuals was relatively steady, even when the scalp hair sampling site was different.