Genotypic characterization and comparison of Streptococcus mutans in American Indian and Southeast Iowa children

Abstract

Early childhood caries is a complex health care issue that has a multifactorial etiology. One aspect of this etiology is the colonization and propagation of acidogenic bacteria at an early age. There have been several bacterial species associated with caries but 1 common species is Streptococcus mutans. Here, we describe genotypic diversity and commonality of Streptococcus mutans recovered from children representing 2 groups with similar socioeconomic demographics: a Northern Plains American Indian Tribe and a Southeast Iowa population. Forty 36‐month‐old American Indian children were selected from a cohort of 239 mothers and children, and forty 2‐ to 5‐year‐old children from Southeast Iowa were selected to compare the genotypic profiles of Streptococcus mutans recovered from each child's plaque. S. mutans isolates were selected from whole mouth plaque samples; DNA was extracted and amplified via AP‐PCR to show specific genotype patterns. These patterns were compared with GelComparIIv6.5 gel analysis software. We found 18 distinct genotypes from 524 isolates; 13 of which were common between the 2 communities. Five genotypes were unique to only the American Indian children while the Southeast Iowa children harbored no unique genotypes. Although the American Indian children had some genotypes that were not present in the Southeast Iowa children, these were not widely distributed among the community. Furthermore, the levels of genotypic diversity and commonality were similar between the 2 populations. This study sets the groundwork for a comprehensive comparison of genotypes and caries among larger subsections of both populations.

Mutans Streptococci and Lactobacilli: Colonization Patterns and Genotypic Characterization of Cariogenic Bacterial Species in American Indian Children

“…The development of the oral microbiome in children is influenced by both maternal and environmental sources (11,12). While other aspects of our overarching study have examined environmental influences that may play a role in the rampant caries observed in this population (4), the focus of microbiological reporting to date has been on genotypic diversity and maternal transmission of S. mutans (16,17). Much research on the influence of the mutans streptococci on caries progression has indicated that the presence of S. mutans and S. sobrinus together results in greater disease risk than S. mutans alone (8,24,27,(41)(42)(43).…”

“…After observing unexpectedly high levels of S. sobrinus in the population (71% of research participants have S. sobrinus present), we expanded the scope of work to include isolation and genotypic analyses of both mutans streptococci (MS) species. We have previously reported on initial acquisition and genotypic diversity of S. mutans in this study population (16,17). The focus of this manuscript is 2-fold: (1) analyses of the presence of S. mutans, S. sobrinus, and lactobacilli in children from this cohort, including exploration of colonization patterns for the three bacterial species of interest;…”

Estimating Genotypic Diversity of Streptococcus mutans Isolated From Caries-Active and Caries-Free Individuals Among Indian Population

“…Napimoga et al [8] in their study demonstrated that more genotypes were found in caries-active subjects than those caries-free subjects. On the other hand, Kreulen et al and other researchers in their study showed a negative correlation between caries activity and the genotypic diversity [9][10][11][12]. The possible association between the biodiversity of S mutans and caries activity among the Indian population deserves attention, as there is paucity in the literature.…”

The Evolving Microbiome of Dental Caries

“…Severe early childhood caries can disproportionately affect American Indian (USA) and First Nation (Canada) children [ 149 , 150 ]. The caries-associated microbiota includes a very high prevalence and high levels of S. mutans [ 151 ], with differences in the genetic diversity of S. mutans compared with other children in the local area [ 152 ]. To further investigate the microbiome of aggressive caries, advanced carious lesions observed in Romanian adolescents who had very limited dental care were compared with a Swedish population with lower caries experience [ 153 ].…”