中文摘要：

目的研究中国汉族人群中C反应蛋白（C—reactive protein，CRP）＋1444C／T、CRP＋1059G／C两种基因多态性与慢性牙周炎的关系，为进一步探讨CRP在牙周炎与冠状动脉粥样硬化性心脏病相关性中的作用和意义提供依据。方法检测126例慢性牙周炎患者（CP组）和113名牙周健康或龈炎者（对照组）的牙周临床指数（附着丧失、探诊深度和探诊出血）、CRP水平及CRP＋1059G／C、CRP＋1444C／T基因多态性分布情况。结果CP组中CRP＋1059C等位基因的频率为6．7％（17／252）；对照组4．9％（11／226），CP组与对照组之间的基因型分布和等位基因频率的分布差异均无统计学意义（0．25〈P〈0．5）。CP组中CRP＋1444T等位基因的频率为6．3％（16／252），对照组5．3％（12／226），CP组与对照组之间的基因型分布和等位基因频率的分布差异亦无统计学意义（0．25〈P〈0．5，0．5〈P〈0．75），当校正了年龄和性别后，CP组血清CRP水平[（1．74±1．67）mg／L]仍显著高于对照组[（0．57±0．39）mg／L]，P〈0．001；对照组中的CRP＋1059GC＋CC基因型携带者的血清CRP水平[（0．34±0．29）mg／L]显著低于CRP＋1059GG基因型携带者[（0．60±0．31）mg／L，P〈0．01]，CP组中则未发现这种差异。CP组和对照组中的CRP＋1444CT＋TT基因型携带者的血清CRP水平均显著高于CRP＋1444CC基因型携带者（0．02〈P〈0．05）。回归分析结果显示，CRP＋1059G／C、＋1444C／T不同基因型和等位基因分布与CP无显著相关性（P〉0．5）。结论CRP＋1059G／C、＋1444C／T基因可能是CRP的功能性基因，尽管牙周炎与心血管疾病显著相关且CRP＋1059G／C、＋1444C／T与心血管疾病有相关性，但是这两个基因位点可能对中国汉族人群牙周炎患者的血清CRP水平影响不显著。

英文摘要：

Objective To investigate the relationship between C-reactive protein （CRP） ＋ 1444C/T, CRP ＋ 1059G/C polymorphisms and chronic periodontitis （CP） in a Han Chinese population. Methods Clinical periodontal parameters [ attachment loss （AL） probing depth （PD） and bleeding on probing（BOP） ] , and serum CRP levels were examined in CP patients （n = 126） and healthy subjects （ n = 113 ）. Results The mean serum CRP level [ （ 1.74 ±1.67 ） mg/L] was significantly higher in the CP group than in the control group [ （0. 57 ±0. 39） mg/L], P 〈 0. 001. In the control group, serum CRP levels were significantly lower in subjects with the CRP ＋ 1059 GC and CC genotypes than those with the CRP ＋ 1059 GG genotype （P 〈 0. 01 ）. There was no significant difference between genotypes in the CP group. In CP and the control groups, serum CRP levels were significantly higher in subjects with the CRP ＋ 1444 CT and TT genotypes compared to those with the CRP ＋ 1444 CC genotype （P 〈0. 5）. The percentage of CRP ＋ 1059 C allele was 6. 7% （17/252） in the CP group and 4. 9% （11/226） in the control group. The percentage of CRP ＋ 1444 T allele was 6. 3% （16/252） in the CP group and 5.3% （12/226） in the control group （P 〉 0. 5 ）. There was no significant difference between groups in both allele frequencies （ P 〉 0. 5 ）. The association of CRP ＋ 1059G/C, CRP ＋ 1444 C/T polymorphisms with CP was not found in a regression model （ P 〉 0. 5 ）. Conclusions The presence of a CRP ＋ 1059C-allele was associated with lower serum CRP levels and the presence of a CRP ＋ 1444T-allele was associated with higher serum CRP levels. However, the data suggested that CRP ＋ 1059G/C, CRP ＋ 1444 C/T polymorphisms were not significantly associated with serum CRP levels of chronic periodontitis patients in ethnic Han Chinese.