CAJ | 학술논문

目的探讨线粒体DNA(mtDNA)4 977 bp缺失(△mtDNA4977)突变比例和拷贝数与线粒体病临床表型复杂程度的关系,为进一步明确病因提供依据.方法选取2003年12月至2013年12月北京大学第一医院160例线粒体病患者,同时选取101名健康体检者为健康对照组.收集两组患者的外周血DNA样品,经限制性片段长度多态性(RFLP)聚合酶链反应检测,未发现常见的热点突变.将所有患者按起病年龄分为低年龄组(＜10岁)和高年龄组(10岁≤年龄＜20岁),运用实时定量聚合酶链反应检测缺失突变比例及拷贝数,利用内参核基因计算每个细胞中mtDNA的数量;采用独立t检验、方差分析和Spearman相关分析进行统计.结果线粒体疾病组的△mtDNA4977突变比例在低年龄组为(2.66±0.63)％,在高年龄组为(3.09±0.74)％,均比健康对照组的同年龄层的突变比例高(t=8.57、4.38,P＜0.01);平均每个细胞△mtDNA4977拷贝数在低年龄组为(2.79 ±0.50)拷贝,在高年龄组为(2.97±0.48)拷贝,均比健康对照组的同年龄层的突变拷贝数高(t=4.50、-3.67,P＜0.01);△mtDNA4977突变比例与线粒体病的复杂程度呈正相关(低年龄组r =0.519,P＜0.01;高年龄组r=0.772,P＜0.01);平均每个细胞的△mtDNA4977拷贝数与线粒体病的复杂程度呈正相关(低年龄组r =0.389,P＜0.01;高年龄组r=0.607,P＜0.05);平均每个细胞的总mtDNA拷贝数与线粒体病的复杂程度呈负相关(低年龄组r=-0.260,P＜0.01;高年龄组r=-0.430,P＜0.05).结论 △mtDNA4977突变比例和拷贝数、总mtDNA拷贝数与线粒体病的复杂程度有相关性,其中以△mtDNA4977突变比例最为密切.
목적 탐토선립체DNA(mtDNA)4 977 bp결실(△mtDNA4977)돌변비례화고패수여선립체병림상표형복잡정도적관계,위진일보명학병인제공의거.방법 선취2003년12월지2013년12월북경대학제일의원160례선립체병환자,동시선취101명건강체검자위건강대조조.수집량조환자적외주혈DNA양품,경한제성편단장도다태성(RFLP)취합매련반응검측,미발현상견적열점돌변.장소유환자안기병년령분위저년령조(＜10세)화고년령조(10세≤년령＜20세),운용실시정량취합매련반응검측결실돌변비례급고패수,이용내삼핵기인계산매개세포중mtDNA적수량;채용독립t검험、방차분석화Spearman상관분석진행통계.결과 선립체질병조적△mtDNA4977돌변비례재저년령조위(2.66±0.63)％,재고년령조위(3.09±0.74)％,균비건강대조조적동년령층적돌변비례고(t=8.57、4.38,P＜0.01);평균매개세포△mtDNA4977고패수재저년령조위(2.79 ±0.50)고패,재고년령조위(2.97±0.48)고패,균비건강대조조적동년령층적돌변고패수고(t=4.50、-3.67,P＜0.01);△mtDNA4977돌변비례여선립체병적복잡정도정정상관(저년령조r =0.519,P＜0.01;고년령조r=0.772,P＜0.01);평균매개세포적△mtDNA4977고패수여선립체병적복잡정도정정상관(저년령조r =0.389,P＜0.01;고년령조r=0.607,P＜0.05);평균매개세포적총mtDNA고패수여선립체병적복잡정도정부상관(저년령조r=-0.260,P＜0.01;고년령조r=-0.430,P＜0.05).결론 △mtDNA4977돌변비례화고패수、총mtDNA고패수여선립체병적복잡정도유상관성,기중이△mtDNA4977돌변비례최위밀절.
Objective To analyze the relationship between proportion of mitochondrial DNA 4 977 bp deletion (△mtDNA4977) or copy number in blood and the clinical complexity to find the pathogenesis of mitochondrial disease.Methods A total of 160 patients with mitochondrial disease and 101 healthy controls of Peking University First Hospital from December 2003 to December 2013 were collected in this study.Their peripheral blood showed no hot-point mutation which detected by polymerase chain reaction-restriction fragment length polymorphism.All the patients were divided into younger group (age ＜ 10y) and elder group (1 0y ≤ age ＜ 20y).The incidence of △mtDNA4977 was detected by real-time quantitative PCR.Internal gene was used to calculate the number of mitochondrial DNA in each cell.Statistical analysis were carried out by the independent t-test,one-way ANOVA and Spearman' s bivariate correlation analysis.Results △mtDNA4977 proportion in the younger group was (2.66 ± 0.63) ％ and in the elder group was (3.09 ± 0.74) ％,both of them were higher than that of healthy control group with the same age (the younger group:t =8.57,P ＜ 0.01;the elder group:t =4.38,P ＜ 0.01);△mtDNA4977 copy number per cell in the younger group was (2.79 ± 0.50) copy and in the elder group was (2.97 ± 0.48) copy,both of them were higher than that of healthy control group with the same age (the younger group:t =4.50,P ＜ 0.01;the elder group:t =-3.67,P ＜ 0.01).The △mtDNA4977 proportion was positively correlated with the complexity of the mitochondrial disease (the younger group:r =0.519,P ＜ 0.01;the elder group:r =0.772,P ＜ 0.01).The △mtDNA4977 copy number per cell was positively correlated with the complexity of the mitochondrial disease (the younger group:r =0.389,P ＜ 0.01;the elder group:r =0.607,P ＜ 0.05).However,the total mtDNA copy number per cell was negatively correlated with the complexity of the mitochondrial disease (the younger group:r =-0.260,P ＜ 0.01;the elder group:r =-0.430,P ＜ 0.05).Conclusions The proportion or copy number of △mtDNA4977 or total mtDNA copy number in blood are correlated with the comolexity of mitochondrial diseases,especially the proportion of △mtDNA4977.