人与动物毛发角蛋白组分的等电聚焦图谱分析

本文用聚丙烯酰胺等电聚焦(PAGIEF)对来自6个目、15个科、20种动物毛发角蛋白组分进行了研究。发现人与动物毛发角蛋白组分的PAGIEF谱型有显著差异;不同种属的动物毛发角蛋白组分的PAGIEF谱型也互不相同,它们各自都有独特的角蛋白PAGIEF谱型。作者认为,本方法可用于鉴定毛发的种属。     

某些灵长类毛发角蛋白的等电聚焦分析

本文用聚丙烯酰胺凝胶等电聚焦(PAGIEF)对分属灵长类的5个科的15种动物毛发角蛋白进行了分析,并用激光光密度计对PAGIEF板进行了扫描。结果表明,各种灵长类毛发角蛋白的PAGIEF谱型均有差异。因此,本方法可以用于灵长类动物之间毛发角蛋白组分的鉴别。     

人发毛干角蛋白电泳谱型的分析

本文用SDS-梯度(5.0～17.0％)聚丙烯酰胺凝胶电泳对150例中国人头发角蛋白组分进行了分析。结果表明,在150例人头发中,有6种不同类型的角蛋白电泳谱型。此1～6型发生频率分别为24％、12％、42％、7.3％、8.0％;及6.7％。用N-(3-芘)马来酰胺标记头发角蛋白巯基,证实人头发不同类型的角蛋白电泳谱型主要区别在低硫蛋白部位。作者认为,人头发角蛋白电泳谱型的差异可为法医学鉴定中的毛发个人识别提供重要的依据。     

毛发角蛋白在法医物证学中的研究进展

毛发角蛋白组成由dNA决定。不同种属和不同个体的毛发角蛋白组成有差异。因此，对毛发角蛋白的研究已引起法医工作者的重视。近年来，国内外有关这方面的研究已有很多报道，本文就毛发角蛋白的研究及其在法医物证学中的应用作一综述。一、毛发角蛋白的组成毛发的主要成分为角蛋白，其存在于毛小皮和皮质中，由3条或7茶多肽链以2一螺旋相扭，通过二硫键连接在一起形成3股或7股的纤维束。用含有DTT（二硫苏糖醇）和流基乙醇的抽提液处理毛发可将毛发角蛋白抽提出来。用不同浓度的醋酸锌（O．OZ～O．1m。l／L）处理毛发角蛋白可获得两种主…     

同一个体发毛角蛋白电泳谱型的分析

用SDS -PAGGE对收集到的 2 0例人体表毛发 (头发、阴毛、腋毛、腿毛 )角蛋白组分进行了分析。结果表明 ,同一个体毛发角蛋白电泳谱型基本相同 ,用激光光密度仪对电泳凝胶板扫描后证实 ,同一个体毛发角蛋白组分相对百分含量也无明显差异 ;人头部不同部位 (顶部、左侧、右侧、额部、枕部 )头发角蛋白的电泳谱型和角蛋白组分相对百分含量也基本相同。同一个体毛发角蛋白组分的分析 ,可为法医物证学鉴定中的毛发个人识别提供重要的依据。     

人与动物毛发角蛋白SDS-聚丙烯酰胺凝胶电泳分析

<正> 法医物证检验中,毛发是常遇到的检材之一。用于鉴别毛发的方法有光学显微镜观察毛小皮、皮质、髓质的形态特征,测定毛发微量元素的含量或用扫描或透射电镜来观察毛发的亚显微结构。但是,这些方法有的易带有主观性,有的技术复杂,并需要昂贵的仪器。近年来,有人采用 SDS—聚丙烯酰胺凝胶电泳(简称 SDS—PAGE)分析毛发角蛋白,鉴别毛发种属。本文用 SDS-PAGE 对人     

测定单根毛发中吗啡含量的放射免疫方法

目的 建立测定单根毛发中吗啡含量的放免方法。方法 用卵清蛋白-琥珀酰吗啡作免疫原,免疫新西兰白兔获得高品质抗血清;HPLC纯化~(125)Ⅰ-吗啡,建立放射免疫方法,测定正常人和吸毒人员单根毛发。结果 抗体亲和常数为3.25×10~(11)L/M,放化纯度为95％,比放射性112μCi/μg;方法的灵敏度为0.01ng/ml。对5例正常人及5例戒毒所吸毒人员的单根毛发进行了检测。单根毛发长度9～24cm,重量为0.7～2.1mg,5例正常人测值为1.75±0.37ng/mg(x±s);5例吸毒人员测值为471±204ng/mg(x±s)。结论 所建方法可准确定量单根毛发中吗啡的含量。     

烫发、梳理和拉伸损伤对头发角蛋白的影响

目的为法医物证学中的头发个人识别提供依据。方法采用烫发、梳理、拉伸等方式对正常人头发进行损伤处理,用十二烷基磺酸钠-聚丙烯酰胺凝胶梯度电泳(SDS-PAGGE)和激光光密度扫描仪对损伤头发角蛋白进行分析。结果三种损伤条件均可导致头发损伤,造成分子量(MW)67000～43000区域头发角蛋白的丢失。结论头发角蛋白的丢失程度随着损伤程度增加而增加。     

毛发中GHB的检测及评价

目的探索毛发中外源性GHB的检测及判断的可行性,为涉GHB的鉴定提供方法和依据。方法建立毛发中GHB的GC/MS分析方法,并通过动物实验,考察毛发中内源性GHB的质量分数范围、外源性GHB在毛发中的时间过程以及给药剂量、毛发颜色与毛发中GHB的质量分数关系。结果豚鼠和中国人黑色毛发中内源性GHB质量分数分别为(3.01±1.41)ng/mg(n=28)和(1.02±0.27)ng/mg(n=20);摄GHB后毛发中GHB质量分数明显增加且与给药剂量呈正相关性;GHB在毛干中呈窄带分布;深色毛发中GHB质量分数高于浅色毛发。结论毛发中GHB的检测适用于GHB滥用和中毒的法医毒物学鉴定;根据毛发中的GHB质量分数和毛发分段分析可判断GHB的来源。     

氯胺酮滥用的毛发分析研究

目的建立毛发中氯胺酮及其代谢物的分析方法并探索氯胺酮进入毛发的机理。方法通过建立豚鼠连续给药(不同剂量)实验模型获取阳性头发和采集氯胺酮滥用者头发,经处理后用GC/MSscan和SIM法分析,以鉴别、确认毛发中氯胺酮及其代谢物。结果豚鼠毛发中氯胺酮的质量分数与给药剂量存在明显的正相关性。毛发中氯胺酮质量分数依白色、棕色、黑色毛发顺序随毛发中黑色素的质量分数增加而增加。豚鼠毛发中氯胺酮与代谢物NK质量分数之比为2.33～12.94,仅在高剂量组的豚鼠毛发中才检测到DHNK,其质量分数与NK接近。15名氯胺酮滥用者黑色头发中均检出原体和代谢物NK,但DHNK少见。豚鼠毛发中代谢物相对质量分数明显高于人。结论本实验结果很好地反映了药物进入毛发代谢过程与药物和黑色素亲和力以及药物的亲脂性密切相关这一规律,但人和动物在药物代谢及进入毛发的难易程度上存在差异。本方法可以用于法庭毒物分析领域头发中氯胺酮的检测。     

Human hair histogenesis for the mitochondrial DNA forensic scientist.

Analysis of mitochondrial DNA (mtDNA) sequence from human hairs has proven to be a valuable complement to traditional hair comparison microscopy in forensic cases when nuclear DNA typing is not possible. However, while much is known about the specialties of hair biology and mtDNA sequence analysis, there has been little correlation of individual information. Hair microscopy and hair embryogenesis are subjects that are sometimes unfamiliar to the forensic DNA scientist. The continual growth and replacement of human hairs involves complex cellular transformation and regeneration events. In turn, the analysis of mtDNA sequence data can involve complex questions of interpretation (e.g., heteroplasmy and the sequence variation it may cause within an individual, or between related individuals. In this paper we review the details of hair developmental histology, including the migration of mitochondria in the growing hair, and the related interpretation issues regarding the analysis of mtDNA data in hair. Macroscopic and microscopic hair specimen classifications are provided as a possible guide to help forensic scientists better associate mtDNA sequence heteroplasmy data with the physical characteristics of a hair. These same hair specimen classifications may also be useful when evaluating the relative success in sequencing different types and/or forms of human hairs. The ultimate goal of this review is to bring the hair microscopist and forensic DNA scientist closer together, as the use of mtDNA sequence analysis continues to expand.     

Mitochondrial DNA amplification success rate as a function of hair morphology

This study examines the amplification success rate of mitochondrial DNA from human head hair with respect to their potential for forensic application. Mitochondrial DNA was isolated using a Chelex-based extraction method and amplified using the LINEAR ARRAY duplex PCR system. The particular focus of this study was to characterize the morphological features of human head hair in order to further the understanding of the factors that influence amplification success rate in hair tissue using the LINEAR ARRAY duplex PCR system. 2554 head hairs from 132 individuals representing four population groups were amplified. The hair samples were characterized as follows: 1251 were identified microscopically as telogen hairs and 1303 were classified as hairs without roots (removed before extraction). Amplification success was assessed as a function of several independent variables: morphological characteristics; telogen root versus no root; donor age; scalp origin; use of cosmetic hair treatments; and race of the donor. The results show that a positive correlation exists between amplification success and the presence of a telogen root. Combining the amplification success with either the original or optimized protocol, telogen hairs result in an overall success rate of 77.5% compared with 65% for hairs with no roots. Controlling for telogen hairs, the findings indicate that the overall success rate is independent of cosmetic hair treatments; medulla structure; shaft length, diameter, and volume; and scalp origin. Conversely, the age of the donor, the race of the donor, and hair pigmentation all contribute to a variation in amplification success rate.     

Accumulation of explosives in hair--part II: factors affecting sorption

This study examines the sorption of eight explosives (2,4,6-trinitrotoluene [TNT]; pentaerythritol tetranitrate [PETN]; hexahydro-1,3,5-trinitro-s-triazine [RDX]; diacetone diperoxide [DADP]; triacetone triperoxide [TATP]; ethylene glycol [EGDN], nitroglycerin [NG]; and 2,4-dinitrotoluene [DNT]) to human hair. The study uses only cut hair, which is exposed to explosive vapor. The vapor transfer studies reported herein indicated that hair did not reach saturation even after 2.5 years of exposure to TNT. While previous studies showed black hair sorbed more explosive than blond or brown, this study reports that red hair sorption is similar to black, while grey hairs, exposed along with black hair from the same individual, sorbed significantly less explosive than the same individual's black hairs. In a study using only black hair, a slight racial bias was observed with sorption greater for Mongoloid hair as compared to Caucasian or Negroid. Only for Mongoloid hairs were enough samples studied to examine for a gender bias, but one was not observed. There was much variability in results in all categories (hair color, race, and gender) that trends were established only in general terms. Hair at different ages was tested for a few individuals. Detailed studies focused on the sorption of TATP and TNT as these appear to be sorbed most differently-TATP mainly on the hair surface and TNT both on the surface and in the cortex. The uptake of high vapor pressure explosives (e.g., TATP) and moderate vapor pressure explosives (e.g., TNT) by hair was rapid and could be detected within about 1 h of exposure. Both explosives were readily sorbed by pure melanin.     

Characterization of Mitochondrial DNA Sequence Heteroplasmy in Blood Tissue and Hair as a Function of Hair Morphology*,†,‡

Abstract: This study characterizes mitochondrial DNA (mtDNA) sequence heteroplasmy in blood tissue and hair as a function of hair morphology. Bloodstains (127 individuals) and head hairs (128 individuals) were typed using the mtDNA LINEAR ARRAY? assay. A total of 1589 hairs were interpreted: 1478 (93%) were homoplasmic and 111 (7%) exhibited heteroplasmy at one or more positions. Seventy‐one percent (82/116) of individuals were homoplasmic, whereas 29% (34/116) exhibited heteroplasmy in at least one hair. The results demonstrate intra‐ and inter‐tissue differences in heteroplasmy within individuals. Sequence heteroplasmy among hairs from each individual varied from 0 to 90%; the frequency does not differ significantly with population group, cosmetic treatment, age, gender, medulla morphology, region of the scalp, hair growth phase, or, when comparing living and deceased donors. However, the results support a correlation between heteroplasmy and hair pigmentation; typically, lighter‐pigmented hairs exhibit a higher incidence of sequence heteroplasmy compared to darker hairs.     

Short tandem repeat (STR) genotyping of keratinised hair. Part 1. Review of current status and knowledge gaps

We present a review of the literature on procedures for obtaining short tandem repeat (STR) genotypes from keratinised hair, being either hair shaft or telogen phase (naturally shed) hairs without associated scalp, follicle or sheath cells. Both the hair shaft and the telogen hair club have been subjected to the DNA-degrading keratinisation process and are more likely to be found at a crime scene than anagen (plucked) or catagen phase hairs. We discuss human hair structure, the human hair growth cycle, the keratinisation process and their implications for DNA extraction procedures, PCR amplification strategies and the interpretation of STR genotypes. Knowledge gaps and areas requiring research are identified and are the subject of a second article in this series.     

Deoxyribonucleic acid (DNA) typing of human leukocyte antigen (HLA)-DQA1 from single hairs in Japanese.

The deoxyribonucleic acid (DNA) typing of human leukocyte antigen (HLA)-DQA1 from single hairs is described. HLA-DQA1 genotypes could be determined from single plucked hair roots. However, it was not easy to type HLA-DQA1 with hair shaft portions. Increase in the specimens of hair shaft portions (over 10 cm in length) to get sufficient DNA caused inhibition of polymerase chain reaction (PCR). Synthetic melanin as well as the one extracted from hairs inhibited the PCR of the genomic DNA template when added to the PCR reaction at the concentrations over than 15 ng/100 microL. Therefore, typability of hair shaft portions seems to depend on the delicate balance of the concentrations of DNA and the contaminated melanin in the final DNA extracts.     

Short tandem repeat (STR) genotyping of keratinised hair. Part 2. An optimised genomic DNA extraction procedure reveals donor dependence of STR profiles

A feasibility study of short tandem repeat (STR) genotyping of telogen phase hairs in particular, and hair shaft in general, is presented. A number of extraction procedures in common use were investigated and the quantities of nuclear DNA (nuDNA) delivered were quantified via a real-time PCR assay. The extracts were subjected to two variations on AmpFlSTR Profiler Plus PCR amplification strategies (extended cycles, two rounds of PCR) and the genotypes compared. Nuclear DNA was found to persist in human hair shafts, albeit at very low levels. Full Profiler Plus profiles consistent with the hair donor were obtained from 100 mg hair shaft samples (bleached and unbleached). These were, however, mixed profiles, indicating low copy number (LCN) contamination in the extracts. Single telogen hair clubs and single hair shafts delivered partial profiles with usually only one allele of heterozygous loci. Telogen phase hairs yielded the same amount of nuDNA (and no more) as hair shafts (either anagen or telogen). Whether hair shafts dissolved or not in lysis buffer had no effect on either the quantitated yield of DNA or on the chance of obtaining a correct genotype. These results provide evidence that genomic DNA resides on the exterior of the hair shaft and we use this information to suggest an optimal procedure for nuDNA extraction from keratinised hair samples: soaking hairs in simple digestion buffers containing Tris-HCl, a salt and a chelating agent without prior cleaning of the hair shafts. It is proposed that cleaning removes most of the recoverable DNA. This procedure was applied to obtain genotypes from 3 cm hair shafts which matched reference profiles from the donors at up to 9 out of 10 AmpFlSTR Profiler Plus STR loci. When the genotyping success was measured by counting the number of matches between the two dominant alleles at each locus for each extract with the reference DNA profile of the hair donor, the success was found to be highly dependent on the donor. The number of matching alleles varied between not less than 10 for one donor to no more than two for another donor. These results may well be linked to the environmental experience of the hairs from each donor prior to removal.     

Correlation of microscopic and mitochondrial DNA hair comparisons

Expert opinions regarding the microscopic comparison of human hairs have been accepted routinely in courts for decades. However, with the advent of mitochondrial DNA (mtDNA) sequencing, an assessment can be made of the association by microscopic hair comparisons in casework between a questioned hair and reference hairs from an individual. While each method can be used separately, the two analytical methods can be complementary and together can provide additional information regarding source association. Human hairs submitted to the FBI Laboratory for analysis between 1996 and 2000 were reviewed. Of 170 hair examinations, there were 80 microscopic associations; of these, only nine were excluded by mtDNA. Importantly, 66 hairs that were considered either unsuitable for microscopic examinations or yielded inconclusive microscopic associations provided mtDNA results. Only six hairs did not provide sufficient mtDNA, and only three yielded inconclusive results. Consistency was observed in exculpatory results with the two procedures. This study demonstrates the utility of microscopic hair examinations and the strength of combining microscopic analysis with mtDNA sequencing.