以單一核苷酸多形性及DNA甲基化來探討protein kinase c α基因與成人氣喘之關聯

Analyzing the single nucleotide polymorphisms and DNA methylation to explore the association between the protein kinase c α (PKC α) gene and adult asthma

林長皜(Chang-Hao Lin)

指導教授 ： 王姿乃

高雄醫學大學/健康科學院/公共衛生學研究所/碩士(2013年)

摘要

全世界估計約有3億人罹患氣喘，是一個不容忽視的健康議題。氣喘的危險因子可區分成兩個種類: 宿主與環境因子，而基因及表觀遺傳學已經被研究證實在宿主因子中扮演著重要的角色。protein kinase c α (PKC α)不僅指的是一個基因，也代表了其表達出來的蛋白質。過去的研究運用了細胞培養技術以及動物試驗，認為PKC α可能對氣喘的發病有所貢獻。因此我們的研究目的是希望藉由一個流行病學的研究設計，結合了單一核苷酸多型性及DNA甲基化的分析，來探討PKC α基因與成人氣喘之關聯性。
本研究招募了524位成人氣喘病患與524位經由性別、年齡配對的社區民眾來進行單一核苷酸多型性的分析。研究中使用的3個tagSNPs (rs3764402 T > C, rs17633401 T > C, rs4520871 T > C ) 是從 HapMap中挑選出來。在DNA甲基化分析的部分，則再招募了30位成人氣喘病患以及14位社區民眾來當對照。
rs4520871的TT基因型比起CC/CT型會顯著增加得到氣喘的風險(adjusted OR= 1.567, 1.037-2.370)。此外rs4520871也會去修飾肥胖跟氣喘的關聯性，儘管交互作用項的檢定並未達到顯著水準。在DNA甲基化的分析中，則觀察到不管是在病例組還是對照組，全部的CpG皆呈現未甲基化的情形。這樣的結果暗示了PKCα啟動子區域的DNA甲基化可能跟氣喘是沒有關聯的。本研究發現rs4520871的基因型跟成人氣喘有顯著的關連性存在，而這個結果可以拿來做為一個預測氣喘風險的新指標。

關鍵字

單一核苷酸多形性 ； DNA甲基化 ； 氣喘 ； 蛋白激酶C alpha

並列摘要

Previous studies have revealed that genetic and epigenetic factors play roles in the development of asthma. Protein kinase c α (PKC α), a member of the PKC family, has been reported to contribute to the pathogenesis of asthma based on the results of the cell culture and animal studies. Our study objectives were to explore the association between the PKCα gene and asthma in adults by a genetic epidemiologic design, consisting of SNP genotyping and DNA methylation analysis.
In the present study, we recruited 524 asthmatic patients and 524 age and sex-matched healthy controls. Three tagSNPs (rs3764402 T > C, rs17633401 T > C, rs4520871 T > C ) for PKCα were selected from HapMap. An additional sample of 30 asthmatic patients and 14 controls was recruited for the methylation analysis.
We observed that the rs4520871 CC/CT genotype significantly increased the risk of asthma (TT versus CC/CT, adjusted OR= 1.567, 1.037-2.370). It also modifies the association between obesity and asthma, although the interaction effect is not significant. A fully unmethylated pattern was found in the 19 CpGs in the promoter region of the PKCα gene, indicating that the level of DNA methylation is not associated with asthma. The rs4520871 genotype is significantly related to adult asthma, and this finding could provide a way to predict the risk of developing asthma.

並列關鍵字

single nucleotide polymorphisms ； DNA methylation ； protein kinase c alpha ； asthma

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