Heritability of Oral Microbial Species in Caries-Active and Caries-Free Twins

Abstract

O ral microbes that colonize in the mouths of humans contribute to disease susceptibility, but it is unclear if host genetic factors mediate colonization. We therefore tested the hypothesis that the levels at which oral microbes colonize in the mouth are heritable. Dental plaque biofilms were sampled from intact tooth surfaces of 118 caries-free twins. An additional 86 caries-active twins were sampled for plaque from carious lesions and intact tooth surfaces. Using a reverse capture checkerboard assay the relative abundance of 82 bacterial species was determined. An integrative computational predictive model determined microbial abundance patterns of microbial species in caries-free twins as compared to caries-active twins. Heritability estimates were calculated for the relative microbial abundance levels of the microbial species in both groups. The levels of 10 species were significantly different in healthy individuals than in caries-active individuals, including, A. defectiva, S. parasanguinis, S. mitis/oralis, S. sanguinis, S. cristatus, S. salivarius, Streptococcus sp. clone CH016, G. morbillorum and G. haemolysans. Moderate to high heritability estimates were found for these species (h 2 = 56%-80 %, p < .0001). Similarity of the overall oral microbial flora was also evident in caries-free twins from multivariate distance matrix regression analysis. It appears that genetic and/or familial factors significantly contribute to the colonization of oral beneficial species in twins.

Bacterial 16S Sequence Analysis of Severe Caries in Young Permanent Teeth

“…C1 are unknown. Surprisingly, S. sanguinis was not identified as health associated, although it has been in many previous studies (5,11,39).…”

“…C1. Recent clinical studies have found strains of S. mitis and S. oralis (1,11), S. cristatus (1,11,42), and C. gingivalis and C. rectus (1) to be associated with oral health. C. matruchotii is associated with calculus formation (34), which occurs at high pH.…”

“…The cariogenicity of Streptococcus mutans and Lactobacillus species in tooth-associated biofilms has long been established based on culture studies (51), but this approach has provided a limited ability to study the role of other species present in biofilm communities. Recently DNA-based methods have been used to study early childhood caries (5,11,23), caries of the primary and permanent teeth in children and young adults (1), root caries in the elderly (42), and advanced dentin lesions (8,10,36). Taken together these studies have confirmed the association of S. mutans and Lactobacillus species with childhood caries, but they also suggest that these species are not sufficient to explain all cases of caries.…”

Twin Studies: Research in Genes, Teeth and Faces

“…Because there is inadequate fluoridation of the water supply and also poor access to dental care, the children in the study are at risk of developing dental caries. The study aims to determine the importance of genetic and environmental influences on the development of dental caries, and involves comparisons between monozygotic and dizygotic twin pairs, as well as comparisons between monozygotic co-twins where one has evidence of dental caries and the other does not (Bretz et al, 2006;Corby et al, 2007). …”

Sistemas neuromodulatórios: implicações fisiopatológicas

“…O sistema dentário enfraquecido não resulta na cárie em si, mas predispõe o indivíduo a uma maior sensibilidade a fatores ambientais como, por exemplo, a ingestão de alimentos com alto teor de açúcar. Estas pessoas tendem a ter características específicas que aumentam a susceptibilidade ao desenvolvimento de cáries como, por exemplo, superfície dentária áspera e irregular, dentina e esmalte enfraquecidos (Deeley et al, 2008), cavidades grandes entre os dentes, presença de bactérias específicas (Corby et al, 2007), composição salivar característica (Jonasson et al, 2007) …”