JL-02多位点探针DNA指纹的法医学应用研究

以自制的JL－02探针进行了DNA指纹分析，对北京地区无关个体进行了调查，计算出任意两无关个体的偶合机率为6．6×10－15；家系分析表明，谱带在亲代与子代间的传递符合孟德尔遗传规律；同一个体不同组织的DNA指纹图相同；混合斑精子DNA指纹图与相应男性血液DNA指纹图完全相同；该探针对0．5μg的基因组DNA杂交，可获得清晰可辩的DNA指纹图。证明了新探针适用于法医物证检验中的个人同一认定及亲子鉴定。     

Archived or directly swabbed latent fingerprints as a DNA source for STR typing

Former studies [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501, J. Forensic Sci. 45 (3) (2000) 687] have shown that even a single skin contact, documented by a latent fingerprint, can transfer enough DNA for a genetic analysis. It was proven in these studies that it is possible to swab fingerprints from surfaces [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501] and use them as a DNA source. Usually, however, discovered fingerprints are removed with scotch tape and placed on evidence cards for further investigation.In this study, we tried to assess the potential use of latent fingerprints as a DNA source for STR typing. The materials (magnetic powder, soot powder and scotch tape) used for visualization and archiving fingerprints in Germany were tested for their PCR inhibitory characteristics. Then, fingerprints were placed on clean glass surfaces, visualized and tested for their usefulness as a DNA source.Obtained DNA was quantified and tested in an STR system. Partly it proved possible to type fingerprints taken directly from the surface as well as fingerprints removed from the surface with scotch tape.     

Recovery of Latent Fingerprints and DNA on Human Skin*

Abstract: The project “Latent Fingerprints and DNA on Human Skin” was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark^®) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark^® (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one‐third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark^® (3.1%) yielded better results than gelatine foil (0.6%).     

Fingerprints as evidence for a genetic profile: morphological study on fingerprints and analysis of exogenous and individual factors affecting DNA typing

Material recovered from 374 fingerprints left by eleven laboratory workers on three different substrates (glass, wood, metal) at a standard pressure time of 30 s, with and without preliminary handwashing, was submitted to morphological, quantitative, and type analysis. Morphological and agarose-gel electrophoresis analysis showed that a non-negligible amount of epidermal corneal cells presented apoptotic alterations. The quantity of DNA recovered from fingerprints ranged between 0.04 to 0.2 ng, and in a significant number of experiments no DNA was detected. Handwashing reduced the amount of DNA recovered from fingerprints. The "shedder status" of the donor was a very important factor, causing inter-individual variations in the amount of DNA left by fingerprints. Spurious alleles from laboratory-based and secondary transfer contamination, stutters, and other artifacts described when analyzing low-copy-number DNA and capable of affecting correct profiles were observed.     

用α-珠旦白-3’HVR探针研究DNA指纹

用α-珠蛋白-3’HVR探针,经Southern印迹法,对100名不相关个体及4个家系的32名相关个体的DNA指纹进行了检测,所产生的DNA图谱具有高度的个体特异性,在被测的所有个体中无一相同。经统计学计算表明,任意两个个体DNA指纹图重合率为10~(-11)。家系分析毒明,DNA片段严格按照孟德尔方式遗传。该探针的应用,将在法医学亲子鉴定和个人同一认定中发挥重要的作用。     

An Optimized DNA Analysis Workflow for the Sampling,Extraction, and Concentration of DNA obtained from Archived Latent Fingerprints

DNA profiles have been obtained from fingerprints, but there is limited knowledge regarding DNA analysis from archived latent fingerprints—touch DNA “sandwiched” between adhesive and paper. Thus, this study sought to comparatively analyze a variety of collection and analytical methods in an effort to seek an optimized workflow for this specific sample type. Untreated and treated archived latent fingerprints were utilized to compare different biological sampling techniques, swab diluents, DNA extraction systems, DNA concentration practices, and post‐amplification purification methods. Archived latent fingerprints disassembled and sampled via direct cutting, followed by DNA extracted using the QIAamp® DNA Investigator Kit, and concentration with Centri‐Sep? columns increased the odds of obtaining an STR profile. Using the recommended DNA workflow, 9 of the 10 samples provided STR profiles, which included 7–100% of the expected STR alleles and two full profiles. Thus, with carefully selected procedures, archived latent fingerprints can be a viable DNA source for criminal investigations including cold/postconviction cases.     

STR genotyping and mtDNA sequencing of latent fingerprint on paper

A systematic study was conducted to investigate whether DNA can be successfully extracted from latent fingerprints deposited on ordinary paper and analysed using short tandem repeat profiling and mitochondrial DNA sequencing. In order to evaluate the performance of latent fingerprint analysis in a criminal case, experiments with varying conditions were carried out to improve our understanding of low copy number (LCN) DNA typing. After optimising the extraction methods to achieve increased sensitivity, the examination of touched paper can routinely yield the STR profile of the individual who has touched it. A fingerprint can therefore be considered as a potential source of DNA for genetic identification. Nevertheless, the findings of our "after enhancement experiment" (using chemically or physically pre-treated fingerprints), and our "mixture experiment" (using fingerprints from three to four people on the same sheet of paper) help to define the limitations of the low copy number PCR technique in forensic casework.     

New optimized DNA extraction protocol for fingerprints deposited on a special self-adhesive security seal and other latent samples used for human identification

Abstract: Obtaining complete short tandem repeat (STR) profiles from fingerprints containing minimal amounts of DNA, using standard extraction techniques, can be difficult. The aim of this study was to evaluate a new kit, Fingerprint DNA Finder (FDF Kit), recently launched for the extraction of DNA and STR profiling from fingerprints placed on a special device known as Self‐Adhesive Security Seal Sticker^® and other latent fingerprints on forensic evidentiary material like metallic guns. The DNA extraction system is based on a reversal of the silica principle, and all the potential inhibiting substances are retained on the surface of a special adsorbent, while nucleic acids are not bound and remain in solution dramatically improving DNA recovery. DNA yield was quite variable among the samples tested, rendering in most of the cases (>90%) complete STR profiles, free of PCR inhibitors, and devoid of artifacts. Even samples with DNA amount below 100 pg could be successfully analyzed.     

Fingerprints and DNA: STR typing of DNA extracted from adhesive tape after processing for fingerprints

An exhibit that is often received for examination in cases of robbery or terrorist activity is adhesive tape. This type of exhibit can often, but not always, be successfully processed for fingerprints. The question arises whether or not it is possible to extract and type DNA after the tape has been sequentially processed for fingerprints. In this work, various donors left fingerprints on the adhesive side of tapes. The tapes were then sequentially processed for fingerprints using an alternate light source, cyanoacrylate fuming, and staining with BY-40 and then crystal violet. DNA was subsequently successfully extracted, amplified and typed for six STR loci.     

Establishing an integrated pipeline for automatic and efficient detection of trace DNA encountered in forensic applications

The analysis of trace DNA is a crucial component in forensic applications. Biological materials containing low-level DNA collected at crime scenes, such as fingerprints, can be valuable as evidence. Automatic detection of biological samples has been largely embraced in forensic applications to meet the increasing throughput requirements. However, the amount of DNA automatically retrieved from trace evidence often tends to be small and unstable, ultimately resulting in poor detection of DNA profiles. Thus, in this work, we introduced a robust DNA extraction and purification platform named Bionewtech® BN3200 (Bionewtech®, Shanghai, China) with the goal of constructing a rapid automatic detection system for trace DNA. The establishment of automatic detection system for trace DNA mainly encompassed two parts: assessing the sensitivity of automatic extraction platform and screening the optimal short tandem repeat (STR) typing kit. The sensitivity of Bionewtech® BN3200 platform based on Ultra-sensitive DNA Extraction kit was initially estimated, demonstrating that this extraction platform might contain large potential in the trace DNA extraction. For the amplification part, three sets of commercial multiplex STR typing kits were selected as candidates, and the amplified products were further genotyped on the Applied Biosystems 3500xl Genetic Analyzer. After comparation, SiFa™ 23 Plex Kit was determined as the most suitable amplification system for trace DNA. Eventually, the newly exploited trace DNA detection system was successfully implemented in the detection of fingerprints derived from glass surfaces with the five-seconds contact time. As a result, the DNA recovered from the fingerprints fluctuated approximately from 57.60 pg to 18.05 ng, in addition, over 70% of the total STR loci were detected in 75% of the fingerprint samples.     

DNA recovery after sequential processing of latent fingerprints on copy paper

Forensic examiners must determine whether both latent fingerprint development and DNA profiling can be performed on the same area of an evidence item and, if only one is possible, which examination offers the best chance for identification. Latent fingerprints can be enhanced by targeting different components of fingerprint residues with sequential chemical treatments. This study investigated the effects of single-reagent and sequential latent fingerprint development processes on downstream DNA analysis to determine the point at which latent fingerprint development should be stopped to allow for DNA recovery. Latent fingerprints deposited on copy paper by one donor were developed using three sequential processes: 1,8-diazafluoren-9-one (DFO) → ninhydrin → physical developer (PD); 1,2-indanedione-zinc (IND-Zn) → ninhydrin → PD; and IND-Zn → ninhydrin → Oil Red O (ORO) → PD. Samples were examined after the addition of each chemical treatment. DNA was collected with cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. DNA profiles were obtained with varying degrees of success, depending on the number and type of treatments used for latent fingerprint development. The treatments that were found to be the least harmful to downstream DNA analysis were IND-Zn and IND-Zn/laser, and the most detrimental treatments were DFO, DFO/laser, and PD. In general, as the number of treatments increase, the opportunities for DNA loss or damage also increase, and it is preferable to use fewer treatments when developing latent fingerprints prior to downstream DNA processing.     

Detection of visible and latent fingerprints using micro-X-ray fluorescence elemental imaging

Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods.     

Possibilities of DNA sex determination in hair roots

Species- and sex-determination on hair roots were simultaneously performed using extracted DNA and a human Y chromosomespecific probe. (pH Y 2.1) After Southern hybridization, Hae III-digested DNA fragments were detected by non-radioactive digoxigenin detection system. DNA was extracted from one to five freshly plucked hair roots. The specific 2.12 kb fragment was successfully detected in male DNA samples from a single hair root. A positive identification of female DNA was more difficult. The hair root DNA was revealed to be stable at room temperature for at least 2 weeks (examination time) and produced the same specific band pattern as the DNA of fresh hair roots. In the blind tests with DNA samples from randomly plucked one to four hair roots, the rate of successful sex-determination was 95.8% on male samples (23 out of 24 samples) and 25% on female samples (4 out of 16 samples).     

DNA Profiles from Fingerprint Lifts—Enhancing the Evidential Value of Fingermarks Through Successful DNA Typing

This study evaluated the compatibility of the most common enhancement methods and lifting techniques with DNA profiling. Emphasis is placed on modern lifting techniques (i.e., gelatin lifters and Isomark?) and historical fingerprint lifts for which limited research has been previously conducted. A total of 180 fingerprints were deposited on a glass surface, enhanced, lifted, and processed for DNA typing. DNA could be extracted and profiled for all the powders and lifts tested and from both groomed fingerprints and natural prints with no significant difference in the percentage of profile recovered. DNA profiles could also be obtained from historical fingerprint lifts (79.2% of 72 lifts) with one or more alleles detected. These results demonstrate the compatibility between different powder/lift combinations and DNA profiling therefore augmenting the evidential value of fingerprints in forensic casework.     

刑事照相常用紫外光源照射对DNA检验的影响研究

目的探究刑事照相常用紫外光源照射不同客体上的血指印和汗潜指印后对DNA检验产生的影响。方法分别使用254nm和365nm紫外光源在不同照射距离,不同照射时间下对不同客体表面制备的原血指印、微量血指印和汗潜指印检材进行照射,随后进行DNA定量分析。结果原血指印经紫外照射后对DNA检验结果无显著影响,微量血指印和汗潜指印经紫外照射对后续DNA检验结果认定影响较大。结论紫外光波长越短、功率越大、照射距离越短、照射时间越长,对DNA检验结果的影响越大。     

Use of deoxyribonucleic acid (DNA) fingerprints for identity determination: comparison with traditional paternity testing methods--Part I

A study involving comparison of the deoxyribonucleic acid (DNA) finger-printing test with traditional methods used for paternity testing is presented. Samples from 191 cases were tested for a series of blood group and polymorphic protein markers. DNA "fingerprints" were then obtained for all samples using the multilocus probes 33.6 and 33.15. The results of DNA fingerprinting correlated well with those of traditional methods and proved to be informative in cases where traditional methods yielded inconclusive or insufficient results.     

The Influence of Selected Fingerprint Enhancement Techniques on Forensic DNA Typing of Epithelial Cells Deposited on Porous Surfaces

Fingerprints deposited at crime scene can be a source of DNA. Previous reports on the effects of fingerprint enhancement methods have focused mainly on fingermarks deposited in blood or saliva. Here, we evaluate the effects of fingerprint enhancement methods on fingerprints deposited on porous surfaces. We performed real‐time quantification and STR typing, the results of which indicated that two methods (iodine fuming and 1,2‐indanedione in ethyl acetate enhancement) had no effect on the quantity of DNA isolated and resultant STR alleles when compared to control samples. DNA quantities and allele numbers were lower for samples enhanced with silver nitrate and 1,2‐indanedione in acetic acid when compared to control samples. Based on DNA quantity, quality, and observable stochastic effects, our data indicated that iodine fuming and 1,2‐indanedione in ethyl acetate were the preferred options for the enhancement of fingerprints on porous surfaces.     

Fingerprint enhancement revisited and the effects of blood enhancement chemicals on subsequent profiler Plus fluorescent short tandem repeat DNA analysis of fresh and aged bloody fingerprints

This study was aimed at determining the effect of seven blood enhancement reagents on the subsequent Profiler Plus fluorescent STR DNA analysis of fresh or aged bloody fingerprints deposited on various porous and nonporous surfaces. Amido Black, Crowle's Double Stain. 1,8-diazafluoren-9-one (DFO), Hungarian Red, leucomalachite green, luminol and ninhydrin were tested on linoleum, glass, metal, wood (pine, painted white), clothing (85% polyester/15% cotton, 65% polyester/35% cotton, and blue denim) and paper (Scott 2-ply and Xerox-grade). Preliminary experiments were designed to determine the optimal blood dilutions to use to ensure a DNA typing result following chemical enhancement. A 1:200 blood dilution deposited on linoleum and enhanced with Crowle's Double Stain generated enough DNA for one to two rounds of Profiler Plus PCR amplification. A comparative study of the DNA yields before and after treatment indicated that the quantity of DNA recovered from bloody fingerprints following enhancement was reduced by a factor of 2 to 12. Such a reduction in the DNA yields could potentially compromise DNA typing analysis in the case of small stains. The blood enhancement chemicals selected were also evaluated for their capability to reveal bloodmarks on the various porous and nonporous surfaces chosen in this study. Luminol. Amido Black and Crowle's Double Stain showed the highest sensitivity of all seven chemicals tested and revealed highly diluted (1:200) bloody fingerprints. Both luminol and Amido Black produced excellent results on both porous and nonporous surfaces, but Crowle's Double Stain failed to produce any results on porous substrates. Hungarian Red, DFO, leucomalachite green and ninhydrin showed lower sensitivities. Enhancement of bloodmarks using any of the chemicals selected, and short-term exposure to these same chemicals (i.e., less than 54 days), had no adverse effects on the PCR amplification of the nine STR systems surveyed (D3S 1358, HumvWA, HumFGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820) or of the gender determination marker Amelogenin. The intensity of the fluorescent signals was very similar and the allele size measurements remained constant and identical to those of untreated bloody fingerprints. No additional background fluorescence was noted. Continuous exposure (for 54 days) to two of the seven enhancement chemicals selected (i.e., Crowle's Double Stain and Hungarian Red) slightly reduced the amplification efficiency of the longer STR loci in profiles of fresh and 7 to 14-day-old bloodprints. This suggests that long-term exposure to these chemicals possibly affects the integrity of the DNA molecules. This study indicates that significant evidence can be obtained from fresh or aged bloody fingerprints applied to a variety of absorbent and nonabsorbent surfaces which are exposed to different enhancement chemicals for short or long periods of time. It also reaffirms that PCR STR DNA typing procedures are robust and provide excellent results when used in concert with fluorescence-based detection assays after fingerprint identification has taken place.     

Infrared spectroscopic imaging for noninvasive detection of latent fingerprints

The capability of Fourier transform infrared (FTIR) spectroscopic imaging to provide detailed images of unprocessed latent fingerprints while also preserving important trace evidence is demonstrated. Unprocessed fingerprints were developed on various porous and nonporous substrates. Data-processing methods used to extract the latent fingerprint ridge pattern from the background material included basic infrared spectroscopic band intensities, addition and subtraction of band intensity measurements, principal components analysis (PCA) and calculation of second derivative band intensities, as well as combinations of these various techniques. Additionally, trace evidence within the fingerprints was recovered and identified.     

Threat mail and forensic science: DNA profiling from items of evidence after treatment with DFO

Two cases of threatening letters with their accompanying envelopes were received to the Division of Forensic Identification unit of the Israel Police. The envelopes, including the stamps, and the letters were initially examined for latent fingerprints by the DFO reagent, known to cause degradation of DNA. Although no latent fingerprints could be visualized on any of the items, the biology laboratory using organic DNA extraction, was successful in defining genetic profiles from all the items employing six STR loci, even after treatment with DFO. In a controlled experiment, a known donor attached a stamp, by licking, to an envelope. This item was treated with DFO and then profiled using STR loci. The results showed that previous DFO treatment on the control stamp before DNA analysis had no negative effects on obtaining the DNA profile of the known donor using STR loci.