Polymorphism Of Sweet Receptor Gene Tas1R2 And Sweet Tooth,Caries Among 5-year-old Children

The incidence of dental caries is involved in multiple factors,such as cariogenic microorganism,host,oral health behaviors,as well as time.Having sweet snack frequently is one of the most important risk factors related to dental caries.Sweetness is mainly mediated by the taste receptor family 1 members(T1Rs),T1R1,T1R2 and T1R3 constitute the taste receptor family 1 members.T1R2 receptor is expressed by Tas1R2 gene.Tas1R2 gene is polymorphic,the individuals with different genotypes of Tas1R2 gene will have different preference for sweet tooth.A C/T single nucleotide polymorphism(SNP)located at locus rs35874116 of Tas1R2 gene strongly was found to be correlate with human taste sensitivity to sweet tooth among the Asian population,and in Europe,individuals who carry genotype TT are prone to have higher risk of caries of permanent teeth.However,up to now,the relationship between Tas1R2 gene polymorphism and caries of primary teeth is unknown.Part ? Relationship between social-behavioral factors and dental caries among 5-year-old children ObjectivesTo explore social-behavioral factors related to dental caries among5-year-old children.MethodsThis cross-sectional study was conducted among 5-year-old children in Qingxiu District,Nanning,South China,from 10/2016 to 10/2017.The children were randomly selected by the cluster sampling method.A questionnaire was distributed to the parents to collect social demographic information and children's oral heath behaviors.Children's dental caries was assessed by decayed,missing,filled surface(dmfs)index.Based on the severity of caries status,children were defined to three groups,caries-free group(dmfs score=0),ECC group(0<dmfs score<6)and S-ECC(dmfs score?6)group.Chi-square,analysis of variance and multiple ordinary logistic regression were used to explore the relationship between social-behavioral factors and dental caries.ResultsTotal of 433 children were enrolled in the study,and 278 of them had dental caries(64.2%)with a mean dmft score of 5.27±3.96,and a mean dmfs score of8.44±8.77.The proportions of ECC group and S-ECC group were 30.7% and33.5%,respectively.The results of multiple logistic regression analysis showed that the severity of dental caries was significantly associated with frequency of sweet snack intake,frequency of bedtime dessert intake,as well as mother'seducation(P<0.005).ConclusionsHaving sweet snack or bedtime dessert frequently of intake and high frequency of Lower educational degree of mother,intake are risk indicators of dental caries among 5-year-old children in Qingxiu district,Nanning,South China.PART ? GENETIC POLYMORPHISMS OF THE SWEET RECEPTOR GENE TAS1R2 GENE AND HIGH-SEVERITY CHILDHOOD CARIES:A CASE-CONTROL STUDYObjectives To explore the relationship between the genotypic polymorphisms of sweet receptor gene Tas1R2 rs35874116 and sweet snack intake and severe early childhood caries among 5-year-old children.Methods Total of 238 samples of oral mucosa were randomly selected from each caries-free group(118)and S-ECC group(118),respectively.The genomic DNA of Tas1R2 gene was extracted,amplified by PCR,purified and then sequenced.Single factor analysis was used analyse the distributions of Tas1R2rs35874116 SNP among different social and oral health behavior variables and caries status.Multiple logistic regression models were applied to assess the the relationship of the genotypic polymorphisms of sweet receptor gene Tas1R2rs35874116 associated with sweet snack intake and severe early childhood caries among 5-year-old children.Results The proportion of rs35874116 alleles in TT genotype was higher in the individuals with a frequency of sweet snack intake ? once/day(81.1% vs.77.1%,P = 0.020),and higher in S-ECC group than in caries free(CF)group(84.7% vs.15.3%,P = 0.037).The results of the final multiple analyses showed TT genotype of rs35874116 d SNP was not only significantly related to the frequency of sweet snack intake(95%CI = 1.124-4.401),but also associated significantly with S-ECC.In addition,frequency of sweet snack intake and bedtime dessert intake,main caregiver and mother's education were also strongly correlate with S-ECC(P<0.005).Conclusions In the Qingxiu District of Nanning sequenced for 5 year old children,Tas1R2 rs35874116 SNP was associated with frequency of sweet snack intake and S-ECC.Intaking sweet snack and bedtime dessert frequently,non-parental caregivers and lower mother's education were also strongly correlate with S-ECC.These findings suggest that we should carry out a specialized and precise oral health promotion polcy on the children with genotype TT of Tas1R2rs35874116.