人外周血白细胞端粒DNA长度与年龄相关性的法医学应用研究

发布时间：2018-02-13 20:37

  本文关键词： 法医学 年龄推断 southern杂交 自溶　出处：《山西医科大学》2007年硕士论文　论文类型：学位论文

【摘要】： 目的探讨人外周血白细胞端粒DNA长度与年龄、性别的关系,及组织自溶对southern杂交法测量结果的影响,以评价通过人外周血白细胞端粒长度推断个体年龄的法医学应用价值。 方法1.端粒—年龄相关性研究:收集97例健康人外周血,按年龄分为20-40岁组、41-60岁组和＞61岁组。酚-氯仿法抽提人外周血白细胞基因组DNA,southern杂交方法测量端粒DNA限制性酶切片断(TRF)长度。2.组织自溶对平均端粒长度测得值的影响:另取6例同年龄(27岁)同性别(男性)人外周血各3ml,将同一血样本平均分成3份(每份1ml)分别于收集后、人工气候箱(25℃、50%)内放置24h、放置72h提取人外周血白细胞DNA,上述方法测出经不同时间自溶后人外周血白细胞端粒DNA限制性酶切片断长度(TRF值)。 结果1.端粒—年龄相关性研究:不同年龄组测得的TRF值随年龄增大依次递减,通过SNK法检验不同年龄组间TRF值差异,结果显示差异显著(P＜0.05)。对各年龄组中不同性别的TRF值进行t检验,发现除20-40岁组人外周血白细胞TRF值的性别差异不显著外(P＞0.05),其余各组TRF值的性别差异均有统计学意义(P＜0.05)。年龄与TRF值的相关线性关系良好(y=-0.054x+11.16 R2=0.64)。分别对不同性别组年龄与TRF值进行线性分析发现,男性为y=-0.069x+11.67(R2=0.71),女性为y=-0.39x+10.62(R2=0.69)。2.组织自溶对平均端粒长度测得值的影响:SNK法对各自溶组间测得的TRF值进行比较,发现24h组与收集后组测得端粒长度差异不大(P＞0.05),72h组与即刻组和24h组都有显著性差异(P＜0.05)。 结论1.端粒—年龄相关性研究:端粒限制性酶切片断长度随个体年龄的增长而缩短,端粒长度的性别差异除20-40组外都有明显的统计学意义,且不同性别端粒的缩短速度不同,男性缩短速度快于女性。2.组织自溶对平均端粒长度测得值的影响:southern杂交法测得的端粒DNA限制性酶切片断长度结果受组织自溶影响变化较大。研究提示人外周血白细胞端粒DNA限制性酶切片断可以作为法医学年龄推断的参考,但应考虑组织自溶的影响。
[Abstract]:Objective to investigate the relationship between telomere DNA length and age, sex of human peripheral blood leukocytes, and the effect of autolysis on the results of southern hybridization, and to evaluate the value of forensic medicine in estimating individual age by using telomere length of human peripheral blood leukocytes. Methods 1.The study of telomere age correlation: the peripheral blood was collected from 97 healthy people. The length of telomere DNA restriction fragment length was measured by phenol-chloroform hybridization method. The mean telomere length was measured by tissue autolysis and the mean telomere length was measured by autolytic assay for the mean telomere length of human peripheral blood leukocytes by phenol-chloroform hybridization method, which was divided into two groups according to their age: 41-60 and > 61.The length of telomere restriction fragment was measured by phenol-chloroform hybridization. In addition, 3 ml of peripheral blood were taken from 6 patients of the same age and 27 years of age) of the same sex (male), and the same blood samples were divided into 3 parts (1 ml each) respectively after collection. The human peripheral blood leukocyte DNA was extracted at 25 鈩，

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