影響DNA傷害程度及修復能力的相關因子之探討

當暴露於環境致癌物時，如空氣污染及吸菸，會使許多種DNA損傷產生，並導致癌症的發生。由環境中的致癌物質及人體內內生性的自由基會傷害基因組而使其不穩定。DNA受損不但會導致癌症的發生，也與許多遺傳性疾病相關。本研究的目的在於評估環境中的各種因素對健康的自願受試者的DNA損傷及修復能力的影響，因此我們徵求了25名身體健康的大學生參加本研究。使用紫外光照射受試者的淋巴細胞以誘發DNA損傷後，使其修復DNA的損傷15、30、60分鐘。在本研究中，利用彗星試驗測量每個時間點的DNA損傷，並計算殘餘損傷百分比(%RD)和修復能力百分比(%RC)來代表DNA修復能力。結果顯示男性及通勤時間較長、有家族病史、有運動習慣、有喝咖啡的習慣、有補充維生素的學生具有較高的DNA損傷及較低的DNA修復能力，然而，不管是比較性別不同或者其他的因素的有無均沒有達到統計上的顯著差異。這可能是因為研究對象為年輕且健康的族群，暴露時間也較短且劑量較低。而特殊暴露對DNA修復能力的影響或許可以在之後針對有職業暴露或環境暴露的族群進行研究來證實。關鍵字：彗星試驗，DNA損傷，DNA修復

關鍵字

彗星試驗； DNA損傷； DNA修復

並列摘要

Exposures to environmental carcinogens, such as air pollutants and smoke, can induce various types of DNA damage and lead to the development of cancer. Free radicals generated from environmental carainogens or endogeneously in human can damage genome and result in genomic instability. DNA damage not only contributes to the development of cancer, but also is associated with many hereditary diseases. The purpose of this study was to evaluate the effects of environmental factors on DNA damage and DNA repair capability in healthy volunteers. We recruited 25 healthy college students to participate in the study. Peripheral blood lymphocytes were collected and irradiated with UV light to induce DNA damage and then incubated for 15, 30, 60 minutes to allow for damage repair. Using comet assay to detect DNA damage at each time point and calculate the percentage of residual DNA damage (%RD) and percentage of repair capacity (%RC) to reflect DNA repair capability. The results showed that male and students with longer traffic time, family history of diseases, sporting habit, coffee drinking, vitamin takings had higher DNA damage and lower DNA repair capacity. However, they did not reach statistical significant, when compared with female or students without above characteristics. It might be that the study subjects were young and healthy population with short exposure time and lower exposure doses. This influence of particular exposure on DNA repair capacity warrants further investigation on occupational or environmentally exposed population. Keywords：Comet assay, DNA damage, DNA repair

並列關鍵字

Comet assay ； DNA damage ； DNA repair

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