Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants|
|Research Institution||Tohoku University|
SAKAMOTO Seizaburo Graduated School of Dentistry, Tohoku University, Professor, 大学院・歯学研究科, 教授 (00235178)
MATSUSAKA Tomonori Graduated School of Dentistry, Tohoku University, Assistant, 大学院・歯学研究科, 助手 (30292220)
CHIBA Junko Dental Hospital, Tohoku University, Assistant, 歯学部・附属病院, 助手 (50197620)
OZAWA Yuki Dental Hospital, Tohoku University, Lecturer, 歯学部・附属病院, 講師 (90125518)
|Project Period (FY)
1999 – 2001
Completed(Fiscal Year 2001)
|Budget Amount *help
¥12,300,000 (Direct Cost : ¥12,300,000)
Fiscal Year 2001 : ¥3,900,000 (Direct Cost : ¥3,900,000)
Fiscal Year 2000 : ¥4,500,000 (Direct Cost : ¥4,500,000)
Fiscal Year 1999 : ¥3,900,000 (Direct Cost : ¥3,900,000)
|Keywords||caries experience / HLA allele / allele frequency / association study / mutans streptococci / lactobacilli / food preference / salivary flow rates / う蝕 / 遺伝 / ヒトDNA / う蝕活動性試験 / 分子疫学 / DMFT / 唾液量 / lactobacilli / DNA抽出 / OMFT / mutans streptococci|
Informed consents were obtained for the parents of the 5th graders (about 10 years old) of local primary schools. The written information to solicit the consent consisted of the aim and methods employed of this study, the obligation of reporting the results to each subject, the reserved right of the parents with regard to their children's involvement in the study.
The subjects were examined for their DMFT and various caries activity tests. The DNA samples, desquamated mucous membrane cells, were collected by gently rubbing the inner cheek of each subject with a cotton swab. The subjects were also asked about their eating between meals and food preference.
Genomic DNA was extracted from cotton swabs, subjected to PCR amplification in a thermal cycler and typed for HLA-DQA1 with Ampli-TypePM+DQA1, HLA-DRB1 with INNO-LiPAHLA-DRBi along with HLA-DRB test kit.
The number of registered subjects was 109 (54 boys and 55 girls). The average of DMFT was 0.59, stimulated salivary flow rates; 1.4ml/m
in, snack intake; 1.5 times/day, and no statistical difference in these factors was found between boys and girls. The subjects were divided into two groups: those with DMFT=0 (59) and those with DMF>10, and the dft, salivary flow rates, SM and LB scores were compared between two groups. Statistically larger SM scores were observed in DMFT>10 group than DMFT=0 group.
The DNA typing of the samples collected from the subjects described above have not yet been compled, therefore, the results of preceded comparable study with Japanese young adults (about 20 years old) are presented below to indicate the possible outcomes of the proposed study.
1) An association was not found between caries experience and HLA polymorphism in young adults.
2) Numbers of mutans streptococci and lactobacilli in the saliva were found to be associated with HLA polymorphism.
3) Stimulated salivary flow rates were associated with HLA polymorphism.
4) The children were generally found to like sweet and dislike bitter taste more than young adults. Less