Distribution of Streptococcus mutans biotypes in five human populations

Area of Science:

• Microbiology
• Dental Public Health
• Human Genetics

Background:

• Streptococcus mutans (S. mutans) are key cariogenic bacteria.
• Understanding the geographic distribution of S. mutans biotypes is crucial for public health.
• Previous research indicates potential variations in S. mutans prevalence globally.

Purpose of the Study:

• To investigate the distribution of S. mutans biotypes across five distinct human populations.
• To identify geographic variations in the occurrence of S. mutans biotypes and their serotypes.

Main Methods:

• Dental plaque samples were collected from US Naval recruits in Florida, California, and Illinois, Hawaiian school children, and Saudi Arabian Navy personnel.
• Cultural and biochemical techniques were employed for the isolation and identification of S. mutans biotypes.
• Bratthall's serotypes (a through e) were used to classify the identified S. mutans biotypes.

Main Results:

• Significant geographic differences in S. mutans biotype distribution were observed, particularly between Saudi Arabians and other groups.
• Biotype c was the most prevalent across all studied populations.
• Saudi Arabian populations exhibited a higher frequency of multiple biotypes and a greater prevalence of biotypes d and e compared to other groups.

Conclusions:

• Geographic location plays a role in shaping the distribution of S. mutans biotypes.
• While biotype c is common globally, specific biotypes (d and e) and multiple biotype colonization are more frequent in Saudi Arabian populations.
• Interpreting population-level caries differences requires considering the multifactorial nature of dental caries beyond just S. mutans biotype distribution.