非渗透性载体手部脱落细胞DNA转移研究  

Study of DNA Transfer from Hand Exfoliated Cells with Non-permeable Carriers

作　　者：袁丽 邹凯南 郝世诚 邓海霄 张金佩 吴丽彬 贺航 YUAN Li;ZOU Kainan;HAO Shicheng;DENG Haixiao;ZHANG Jinpei;WU Libin;HE Hang(Shanghai Key Laboratory of Scene Evidence,Shanghai Research Institute of Criminal Science and Technology,Shanghai 200083,China;Key Laboratory of Evidence Science of Ministry of Education,China University of Political Science and Law,Beijing 100088,China)

机构地区：[1]上海市刑事科学技术研究院&上海市现场物证重点实验室,上海200083 [2]中国政法大学证据科学教育部重点实验室,北京100088

出　　处：《中山大学学报（医学科学版）》2024年第5期818-825,共8页Journal of Sun Yat-Sen University:Medical Sciences

基　　金：上海市现场物证重点实验室开放课题基金(2021XCWZK12)。

摘　　要：【目的】在塑料方向盘或鼠标等非渗透性载体上开展手部脱落细胞的一次转移、二次转移等研究。【方法】首先检验实验室DNA灵敏度、混合DNA分型的检出限,以了解本实验室检验微量DNA的能力。用生物物证粘取器直接粘取志愿者超1 h未洗的手、粘取志愿者洗手后30 min用利手触摸的载体、粘取志愿者洗手后30 min相互握手后立即或30 min后接触的载体、粘取第二人触摸第一人日常使用的载体后再转回第一人触摸10 min的载体,以及模拟在日常检验样本中混入他人手部脱落细胞,对上述检材进行DNA检验。【结果】本实验室检验平台可以从低至0.020 ng的DNA中获得完整分型,可以从1:9的混合DNA中检出次要成分。实验结果显示不洗手条件下有85%检材检出完整DNA分型;志愿者洗手后30 min利手触摸的载体有77%能够检出完整一次转移DNA分型,个体可区分好脱落者和差脱落者,男女性别之间、载体之间没有统计学差异;志愿者洗手后30 min相互握手后立即接触的载体有75%检出了对方基因型(即二次转移DNA),检出STR基因座从0个至23个,而在手部脱落细胞交换后30min再触摸的载体上检出二次转移机会和检出基因座数目均大幅降低;在日常检验样本中混入他人的手部脱落细胞中未检出脱落细胞DNA;当两人轮流用手接触载体时,DNA图谱的主要贡献者并非都为最后接触者。【结论】可以从非渗透性载体上检出一次或二次转移DNA,根据手部脱落细胞沉积程度,个体分为好脱落者和差脱落者,这也是影响转移DNA检出情况的重要因素。结合实验室DNA检验灵敏度,在手部接触性检材检出DNA时,结果解释需考虑活动层级可能发生的二次转移。【Objective】To investigate primary and secondary transfer of exfoliated cells from human hands on non-porous substrates such as plastic steering wheel or computer mouse.【Methods】DNA detection sensitivity and detection limit for mixed DNA profiling were examined to understand our laboratory’s ability to test for trace DNA.Forensic swabs were used to collect samples from volunteers’one-hour-long unwashed hands,substrates touched by volunteers’dominant hand 30 min after hand washing,substrates touched by volunteers 30 min after washing their hands and then immediately or 30 min following shaking hands,and individual A’s daily-use substrates touched by individual B and then by individual A again.Simulations were conducted to assess the potential for introduction of another person’s exfoliated cells from hands into routine casework samples.【Results】Our laboratory can obtain a full DNA profile from as little as 0.020 ng of DNA and detect minor components in a 1:9 mixed DNA sample.85%of samples from unwashed hands yielded a full DNA profile.Primary transfer of a full DNA profile was found in 77%of substrates touched by volunteers’dominant hand 30 min after hand washing,allowing differentiation between good and poor shedders,with no significant difference in genders and substrate types.75%of substrates touched 30 min after hand washing and then immediately following handshaking yielded the other individual’s DNA profile(secondary transfer),with the number of short tandem repeat(STR)loci detected ranging from 0 to 23;the percentage and number decreased substantially when the substrates were touched 30 minutes later.No foreign DNA was detected in routine casework samples with introduced exfoliated cells from hands.When two individuals took turns touching items with their hands,the major contributor to the DNA profile was not always the individual who made the last contact.【Conclusions】Primary and secondary DNA transfer can be detected on non-porous substrates,and based on the deposit of hand ex

关 键 词：法医物证 脱落细胞 转移DNA 非渗透性载体 活动层级 交通车辆 

分 类 号：D918.9[政治法律—法学] R8[医药卫生—临床医学]