Diversity in the bacterial communities of oral saliva from different genders of the Tibetan Population

Abstract

Objective

This study aims to investigate gender-based differences in oral bacterial community structure and diversity among Tibetans in Guoluo Prefecture, Qinghai, China, in order to support future research on the prevention and treatment of oral and systemic diseases.

Methods

Oral saliva samples from 19 Tibetan males and 19 females were analyzed using Illumina high-throughput sequencing of the 16S rRNA gene. Species diversity indices and community composition were compared between genders.

Results

A total of 9556 Species Observed (Sobs) were collected, with 5264 Sobs from Tibetan males (14 phyla, 128 genera) and 4292 Sobs from females (13 phyla, 108 genera). Species diversity analyses revealed that the Shannon and ACE indices of the oral bacterial communities of Tibetan males (2.45–4.07, 202.29–406.01) were significantly higher (P < 0.05) as compared to the females (1.77–3.55, 131.58–410.31). Community composition analysis demonstrated that the predominant phyla of the oral saliva samples were similar in Tibetan males and females and included Firmicutes, Bacteroidota, and Actinobacteriota. Gender differences were detected in the dominant oral bacterial genera, with Neisseria, Rothia and Prevotella being the genera exhibiting key differences. In Tibetan males, the dominant genera were Streptococcus (12.27 %–60.22 %), Veillonella (1.98 %–37.13 %), Prevotella (12.27 %–60.22 %), Actinomyces (1.07 %–25.41 %), Rothia (0.96 %–11.16 %), Porphyromonas (0.37 %–13.72 %), and Gemella (0.33 %–10.12 %). For females, the predominant genera included Streptococcus (11.49 %–54.24 %), Neisseria (0.46 %–49.22 %), Rothia (5.05 %–29.70 %), Porphyromonas (0.11 %–21.48 %), Gemella (1.01 %–13.31 %), Granulicatella (1.18 %–14.93 %), Prevotella (0.06 %–29.18 %), Haemophilus (0.41 %–6.97 %), and Veillonella (0.26 %–13.72 %).

Conclusions

Gender-specific variations in oral microbiota composition highlight potential implications for understanding oral and systemic disease susceptibility in Tibetan populations. These findings provide a foundation for targeted preventive and therapeutic strategies.