著者

木下 勝博

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.6, no.2, pp.65-83, 2002 (Released:2009-10-14)

参考文献数

101

被引用文献数

1 1

---

Tracking phenomenon, to put it plainly, is the phenomenon to form the carbonized electrical track and lose insulation in the part with potential difference on the surface of insulating materials. Tracking resistance means the difficulty occuring the tracking phenomenon of the organic insulation materials. Studies on the tracking phenomenon and the method of evaluating tracking resistance has been often reported on so far. But, there are only a few comprehensive researches and commentaries which include tracking phenomenon and the fire which occurs by the tracking phenomenon. Hence, I decided to explain tracking phenomenon of the organic insulating materials and the phenomenon that developed concerning the fire which develops and is called, tracking fire. Tracking phenomenon is discussed first. Next, cases of tracking fire in electric wiring and the wiring utensil and the studies on the cause of tracking fire are explained. Furthermore, prevention of tracking fire and future problems are also discussed.

著者

岩本 良二 太田 奈穂樹 相場 伸 村川 雄大 棟方 栄治

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.6, no.2, pp.99-108, 2002 (Released:2009-10-14)

参考文献数

24

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This paper presents a study of the intra-individual variation of pubic hairs. Seventy pubic hairs were pulled from seven sites around the outer genital area of each of five Japanese males; sixty were obtained from six sites on each of four Japanese females, and fifty from six sites on one additional Japanese female. These hairs were examined with respect to twenty-two morphological characteristics. These morphological data were studied in relation to each site and analyzed by the statistical method of cluster analysis.   It appeared that a pubic hair's length, luster, diameter, medullary index, disease and scale damage bore some relation to the site from which it was obtained. Dendrograms produced through the cluster analysis showed a hierarchy of similarities among all pairs of pubic hairs. Similar hairs were placed together into several large or small groups within the same person. Some groups contained pubic hairs from many sites, whereas others were almost exclusively from only one site. This means that some sites have different characteristics from other sites. Pubic hairs obtained from the penis area, scrotum and labium majus area showed greater dissimilarity than other sites within the same person.   Therefore, in forensic hair comparison, known pubic hair samples should be obtained from many different sites. For males, at least thirty-five pubic hairs should be collected from seven sites (center, left and right abdomen; upper, left and right area surrounding the penis; and scrotum). For females, at least thirty pubic hairs should be collected from six sites (center, left and right abdomen; mons pubis; left and right labium majus).

著者

雨宮 正欣 長井 辰男

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.4, no.2, pp.95-98, 2000 (Released:2010-02-05)

参考文献数

14

被引用文献数

1 3

---

Though easiness and availability of a screening test are important factors, its correctness is most important for a drug abuser's arrest according to screening results. The use of Triage® in screening tests to detect stimulants was examined.   Abusers' urine samples contained methamphetamine at the concentration of which ranges from 1μg/ml to 479 μg/ml, and 66 μg/ml(n=68) on the average. Triage® showed negative reaction at 1000 μg/ml to 1500 μg/ml, even though there was a high concentration of methamphetamine. Triage® gives false negative result, even when there is a very high concentration of stimulant present in the urine. We should take this into consideration.

著者

廣田 昭久 横田 賀英子 和田 純一郎 渡辺 昭一 高澤 則美

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.5, no.1, pp.33-53, 2000 (Released:2009-11-27)

参考文献数

81

被引用文献数

9 7

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In the present study we investigated heart rate and heart rate variability (HRV) in the guilty knowledge test (GKT). Participants were instructed to “steal” envelopes and hide them. Participants were then presented with questions focusing on certain aspects of the particular envelopes they had stolen. They were requested to respond with “no” to every question, thus denying their knowledge about the critical items. Heart rate, SCR, and HRV components of high-frequency (HF) and low-frequency (LF) were measured during the GKT examinations. Results showed that heart rate decreased in the critical items. They also showed that decrement of heart rate was most distinctive about 10-15 seconds after the onset of the questioning of the critical items. The results indicated that there is a characteristic response pattern between heart rate and HRV concerning the critical items. That is, heart rate decrement is accompanied by increment of HF component and decrement of LF component. Also, in order to examine which method would serve as the most effective measure for psychophysiological detection of deception, we compared among three different analytical methods: fast Fourier transform (FFT) analysis, peak-to-valley method, and complex demodulation (CDM) method, in assessing HRV, respectively. Results showed that the CDM method traced both HF and LF amplitudes were most effectively, and therefore would be the best indices for detection. Some hypotheses were discussed concerning psychophysiological responses in detection of deception, one of which was the implication that subjects might have adopted passive coping, in other words, hemodynamic reaction pattern-II, when presented with the critical items, because of the particular cardiovascular response pattern shown in the psychophysiological detection of deception.

著者

原 忠嗣

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.9, no.1, pp.59-63, 2004 (Released:2007-12-05)

参考文献数

2

---

At present, the footprint identification is conducted by the number of distinguishing characteristics point in the footprint. Life size footprints photos were usually used and magnified footprints photos were seldom used.   If these characteristics parts were magnified and showed minute distinguishing marks more evidential values could be added to them.   The method developed in this paper was to take pictures of magnified characteristic parts of both footprints retrieved at a crime scene and ones taken from shoes themselves in the same magnifying power, followed by enlarging photos from the negatives and comparing the minute distinguishing marks by superimposition.   This method enables us to make magnified footprints photos of about 5 to 30 magnifications easily in a short time.   By inspecting the magnified footprint photos, it was proved that one part which was simply evaluated as one characteristic in the present method actually had many distinguishing marks.

著者

Yoshiteru Marumo

出版者

Japanese Association of Forensic Science and Technology

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.7, no.2, pp.95-111, 2003 (Released:2009-04-11)

参考文献数

115

被引用文献数

6 11

---

Soil can provide important information to criminal investigations as transfer evidence because many criminal cases take place under circumstances such that soil transfers to a criminal or victim. The variation in soils from place to place makes soil valuable evidence to prove linkage between a suspect and a crime scene. Soil is a complex mixture with a variety of mineralogical, chemical, biological, and physical properties. Considering such complexity, a variety of methods have been developed for forensic science purposes. Because minerals are an important component of soils, mineralogical examination is essential in forensic soil identification. Additionally, many other methods can be applied to raise the discriminating power, but not all kind of methods need to be used. What is important is that examiners select an appropriate combination of methods by considering the context of the soil samples. This report summarizes a wide range of reports on the analysis of soil components and of closely related materials such as plant fragments, pollen and spores, and diatoms, with emphasis on the importance of screening tests consisting of several simple techniques. The soil formation process involves parent materials, temperature, water condition, vegetation, time, and the chemical processes of solution, oxidation, reduction, and even human activities. The history of a soil's development as the results of such complex soil formation process is strongly reflected in soil color. The systematic observation of multiple soil colors is especially useful for screening.

著者

宮沢 正 中島 邦生 南 幸男 池田 昌彦

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.2, no.2, pp.95-98, 1997 (Released:2010-06-10)

参考文献数

10

---

The pinpoint condensation technique using perfluorated polymer film was applied to the identification of lysergic acid diethylamide (LSD). Rapid solvent elimination for condensation of LSD into a small single residual at room temperature was performed by solvent evaporation on perfluorated polymer film, and the residual was measured by the microscope/FTIR technique. This sample condensation method provided high sensitivity for IR analysis. The detection limit was 2ng. When interfering substances did not exist in the extracted solution from blotter paper of LSD, the extract was able to be measuered simply and rapidly by microscope/FTIR technique. If isolation by preparative TLC was needed, the best elute was ethyl acetate or isopropanol which did not elute interfering substances from TLC plate into the eluent. More than 5 μg of LSD would be detectable by this technique after preparative TLC. We were able to identify LSD by this technique with preparative TLC from blotter paper containing more than 10 μg of it. This technique was useful to identify LSD sensitively from forensic samples.

著者

森好 浩行 森川 俊雄 安部 隆芳 中山 英樹 中木 真一 糸原 幸次

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.3, no.2, pp.57-62, 1998 (Released:2010-06-17)

参考文献数

8

---

Positive identification of unknown skeletonized victims lacking clinical records generally difficult. However, if their facial photographs could be obtained, their unknown skulls could be identified by the cranio-facial superimposition. The last two decades, video superimposition technique has widely been used for identifying unknown skulls. Although video superimposition will be the most superior technique, the means are expensive and unusual installation. Therefore, in Japanese local forensic science laboratories, the video superimposition installation is not popularly used. To solve the problem the authors attempted to identify an unknown skull by an inexpensive means of superimposition using a personal computer, a digital camera, an image-scanner and a photo-retouch-soft(Adobe Photoshop). The use of the personal computer with Adobe Photoshop allowed to capture a digitized image of the facial photograph with the image-scanner and an image of the skull with the digital camera. With the Adobe Photoshop, the digitized skull's images can be converted to a transparency so as to be overlaid on the digitized facial image and then be adjusted to their respective size. In order to investigate the reliability of our cranio-facial superimposition method, one skull was superimposed on facial photographs of the true person and 14 other people. The true person was correctly identified as the skull's owner and the 14 others were excluded. Hence, the authors insist that this method will be useful to demonstrate the consistency between skull and facial photograph for personal identification.   The application of this superimposition method to three actual cases was also described.

著者

吉野 峰生

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.2, no.2, pp.45-55, 1997 (Released:2010-06-10)

参考文献数

102

被引用文献数

3 3

---

This article constitutes a review of the literature and an evaluation of the anatomical relationships between skull and face including the soft tissue thickness at various anthropometrical points of the skull, along with a comparison of the methodologies involved in the three techniques, that is, photographic, video and computer-assisted superimposition techniques used in forensic science. In addition, an evaluation of cosistency between skull and face is discussed from the aspect of personal identification.   Forensic examiner must be well versed in the anatomy of skull and face for effective utilization of the superimposition technique. When evaluating anatomical consistency between these parts, special attention should be paid their outline, the facial tissue thickness at the anthropometrical points, and positional relationships between skull and face. Data on the thickness of facial soft tissue has been accumulated for each race, Caucasoid, Negroid and Mongoloid. The positional relation of the eyebrow and eye to the orbit, the ala to the nasal aperture, and the lips to the teeth has been investigated by many researchers.   Over the last two decades, video superimposition technique has widely been used for identifying unknown skull. The video superimposition presents enormous advantage over the conventional photographic superimposition. This technique allows the fade-out of either the skull or facial image on the monitor for overall assessment of how well the two images match. This also allows the various sectioning images of the skull and facial images for evaluating the positional relationships between the skull and face. In this technique, however, the anthropometrical examination including soft tissue thickness could not directly be performed on the TV monitor.   On the other hand, in the last ten years, the computer-assisted cranio-facial superimposition has been developed. The use of a video-computer with appropriate software allows to take the images of the skull and facial photograph with only one camera and to directly compare the digitized both images on the monitor. The computer technology has also been used to determine the size of natural head and optimum objective length. The software such as the polynomial functions and Fourier harmonic analysis has been applied to evaluate the fit between the outline of skull and facial photograph.   It is suggested that the outline from the forehead to the gnathion in the lateral or oblique view is the preferable portion for personal identification, and the cranio-facial superimposition method is reliable for personal identification when two or more facial photographs taken from different angles are used in the examination. The computer-assisted skull identification system using video superimposition is useful to demonstrate the cosistency between skull and facial photograph because the quantitative data including anthropometrical measurements obtained from this system provide objective and reliable results in skull identification.

著者

平 伸二

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.3, no.2, pp.21-35, 1998 (Released:2010-06-17)

参考文献数

90

被引用文献数

4 4

---

This article reviewed previous studies concerning psychophysiological detection of deception in which event-related brain potential(ERP) had been recorded as a response index. The usual dependent measures in detection studies are autonomic activities such as respiratory, electrodermal, and cardiovascular responses that are assumed to be correlates of the emotional state induced by crime relevant questions. Recently, however, researchers in this field have emphasized the importance of cognitive factors rather than emotional ones to detect guilt and this trend facilitates the use of ERP as a detection measure.   Several ERP components have been identified and each functional significance during human information-processing has been well described. In the ERP-based detection studies, a component such as P3, N400, or CNV(contingent negative variation) have been used as a detection index. The P3 is elicited by rare and meaningful events that are relevant to the participant's task. The N400 component is elicited by semantic anomalies such as words that complete sentences falsely. The CNV has been variously described as related to expectancy, motivation, and attention. Although these three ERP components seem valid detection measures, the most promising index in the field practice is the P3 component because of its relative ease of recordings and large amplitudes. Moreover, in laboratory studies, correct detection rates by the P3 component are slightly higher than the rates by the conventional autonomic measurements.   Several merits of using an ERP component as a detection index are summarized as follows: 1) advancement and elaboration in judgment of test results because ERP are specifically time locked to an event, 2) an improvement of the correct detection rate, 3) an improvement of test objectivity and reliability, and 4) counteracting countermeasures. Before the practical use of ERPs in the psychophysiological detection of deception, however, a method of artifact-free measurement of ERPs and a definite criterion of judgment for individuals must be established.

著者

白石 智子 関口 和正 大森 毅

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.7, no.2, pp.159-165, 2003 (Released:2009-04-11)

参考文献数

16

被引用文献数

5 5

---

‘OC-Hemocatch’, an immunochromatographic test for the detection of fecal occult blood was evaluated for the forensic identification of human blood. ‘OC-Hemocatch’ showed positive results for human blood to a dilution of 1:500,000 and provides the strongest detection line for a dilution of 1:20,000. On the other hand, the human blood diluted to 1:100 was negative for ‘OC-Hemocatch’ because of the high dose hook effect. While heating at over 150°C, long term exposing to sunlight, washing and bleaching of bloodstains prevented the detecting of human hemoglobin using ‘OC-Hemocatch’, contamination of blood with various body fluids did not affect it. Furthermore, ‘OC-Hemocatch’ detected human hemoglobin from old bloodstains stored for 15 years at room temperature when 5% ammonia was used for extraction. These results demonstrate that ‘OC-Hemocatch’ can be effectively applied to forensic identification of human blood.

著者

瀬戸 康雄 井浦 一光 糸井 輝雄 柘浩 一郎 片岡 美江子

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.9, no.1, pp.39-47, 2004 (Released:2007-12-05)

参考文献数

9

被引用文献数

7 8

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The detection performance of an Environics OY M90 chemical warfare agent detector was investigated with nerve gases, blister agents, blood agents and related compounds. The vapors of sarin, soman, tabun, dimethylmethylphosphonate and also acetone were recognized as “NERVE”, those of mustard gas, lewisite 1 and also 2-mercaptoethanol as “BLISTER”, and those of hydrogen cyanide and cyanogen chloride as “NERVE” or none and not as “BLOOD”. Neither the vapors of solvents, such as methanol and n-hexane, nor the mixture of sarin and acetone, both of which were recognized as “NERVE”, were categorized as any chemical agent. The time from the sample drawing until the alarm indication varied with the species of chemicals, from a few seconds for sarin to a half minute for lewisite 1. Except for mustard gas, once chemical agents were drawn into the detector for two minutes, the alarm indication continued for longer than 10 minutes and it took several minutes for the maximum intensity to be reduce by half.

著者

木下 勝博

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.6, no.2, pp.65-83, 2002

被引用文献数

1

---

&nbsp;&nbsp;Tracking phenomenon, to put it plainly, is the phenomenon to form the carbonized electrical track and lose insulation in the part with potential difference on the surface of insulating materials. Tracking resistance means the difficulty occuring the tracking phenomenon of the organic insulation materials. Studies on the tracking phenomenon and the method of evaluating tracking resistance has been often reported on so far. But, there are only a few comprehensive researches and commentaries which include tracking phenomenon and the fire which occurs by the tracking phenomenon. Hence, I decided to explain tracking phenomenon of the organic insulating materials and the phenomenon that developed concerning the fire which develops and is called, tracking fire. Tracking phenomenon is discussed first. Next, cases of tracking fire in electric wiring and the wiring utensil and the studies on the cause of tracking fire are explained. Furthermore, prevention of tracking fire and future problems are also discussed.<br>

著者

高津 正久 福島 正雄 Ulrich Gerber

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.6, no.1, pp.57-63, 2001 (Released:2009-11-27)

参考文献数

7

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Numerous kinds of fingerprint powder such as aluminum flake have been successfully used for latent fingerprint detection in crime scene investigation. These fingerprint powders are hazardous to human health, especially for crime scene investigators, and sometimes seriously damage valuable furniture, electronic devices and precision instruments.   In this paper, dogtooth violet starch, wheat flour, black tea, green tea, green laver were ground into fine particles less than 80 micrometers using a ball mill grinder. The shape of these fine powders were observed by scanning electron microscope (SEM), and their adherence to the skin ridge deposits was evaluated. Each powder detected a latent fingerprint 4 hours after imprinting on a glass plate, but they did not give good results for older or weaker fingerprints.   Green laver, which is a marine plant of the green algae family, has a single cell layer structure. An improved green laver powder, produced by freeze-drying followed by grinding, contains a remarkable amount of thin plate particles. This characteristic feature of the improved green laver powder made it more adhesive, revealing even weak latent fingerprints 3 days after imprinting on a glass plate. The quality of lifted fingerprints was good enough to be used for fingerprint identification.

著者

日本鑑識科学技術学会 [編]

出版者

日本鑑識科学技術学会

巻号頁・発行日

0000

著者

瀬田 季茂

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.1, no.1, pp.1-10, 1996 (Released:2010-06-10)

参考文献数

79

著者

益子 賢蔵 宮本 卓之

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.2, no.1, pp.21-25, 1997

---

&nbsp;&nbsp;The method studied in this paper is developing latent fingerprints based on ruthenium tetroxide (RuO₄) method. Ruthenium tetroxide fuming promptly react with various organic compound, particularly oils or fats contained in sebaceous secretions in latent print and producing brownish black or black ruthenium dioxide (RuO₂).<br> &nbsp;&nbsp;Ruthnium Tetroxide is yellow, volatile crystails (melting point; 25.5&deg;C, boiling point; 100.8&deg;C) at room temperature.<br> &nbsp;&nbsp;Conventional methods using RuO₄ have been almost impractical because it is very difficult to handle by its strong oxidizability. Additionally because of the two liquid method, it is not only troublesome to produce RuO₄ fumes immediately before developing latent fingerprints, but also is difficult to produce necessary ammounts of RuO₄ fumes.<br> &nbsp;&nbsp;In this method, these problems were resolved by utilizing a saturated hydrocarbon halogenid solution of RuO₄<br>

著者

岩本 良二 太田 奈穂樹 相場 伸 村川 雄大 棟方 栄治

出版者

Japanese Association of Forensic Science and Technology

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.6, no.2, pp.99-108, 2002

---

This paper presents a study of the intra-individual variation of pubic hairs. Seventy pubic hairs were pulled from seven sites around the outer genital area of each of five Japanese males; sixty were obtained from six sites on each of four Japanese females, and fifty from six sites on one additional Japanese female. These hairs were examined with respect to twenty-two morphological characteristics. These morphological data were studied in relation to each site and analyzed by the statistical method of cluster analysis.<br>   It appeared that a pubic hair's length, luster, diameter, medullary index, disease and scale damage bore some relation to the site from which it was obtained. Dendrograms produced through the cluster analysis showed a hierarchy of similarities among all pairs of pubic hairs. Similar hairs were placed together into several large or small groups within the same person. Some groups contained pubic hairs from many sites, whereas others were almost exclusively from only one site. This means that some sites have different characteristics from other sites. Pubic hairs obtained from the penis area, scrotum and labium majus area showed greater dissimilarity than other sites within the same person.<br>   Therefore, in forensic hair comparison, known pubic hair samples should be obtained from many different sites. For males, at least thirty-five pubic hairs should be collected from seven sites (center, left and right abdomen; upper, left and right area surrounding the penis; and scrotum). For females, at least thirty pubic hairs should be collected from six sites (center, left and right abdomen; mons pubis; left and right labium majus).<br>

著者

太田 奈穂樹 岩本 良二 相場 伸 村川 雄大 棟方 栄治 川口 龍一

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.9, no.2, pp.95-102, 2004 (Released:2007-11-07)

参考文献数

8

被引用文献数

1

---

In a recent murder case, many feathers were left at the crime scene and collected for analysis. It seemed they were likely left from the suspect's torn jacket. Goose and duck downs are commonly used for clothes and bedclothes, especially in high quality goods where goose feathers are used most often. Unfortunately, at the time of the murder there were few studies in Japan about down identification. This paper presents how to identify goose and duck downs by microscopy.   Ten downs were removed at random from each stuffed bird from sixty-one species at the prefectural museum. Ten downs were removed at random from ten geese and ten ducks, respectively, at the prefectural farm. Therefore, the authentic sample set (family or species known) included ten downs each from eighty-one birds, representing sixty-three species. In addition, two hundred goose downs and two hundred duck downs were obtained from samples supplied by the Japan Spinners Inspecting Foundation in Tokyo.   These down samples were examined microscopically with respect to eight morphological characteristics: full length, color, node shape, maximum node width, maximum node interval, node distribution, node density (number of nodes per mm) and pigment distribution. Morphological data from geese were compared with ducks and analyzed statistically using F-test.   Duck and goose downs are identified primarily by their triangular nodes. In birds of the sixty-three species other than those from the duck and geese species, triangular nodes were found only in the Anatidae, Columbidae and Psittacidae families. Fortunately, it was quite simple to distinguish the families by the node distribution along the shaft of the barbules. For example, the Anatidae family has triangular nodes only toward the tip of the barbule, the Columbidae family has them mainly toward the base of the barbule, and the Psittacidae family has them uniformly distributed along the shaft of the barbule. Based on feather nodes, both goose and duck can be placed in the Anatidae family. Nevertheless, they can be distinguished. Goose has wider maximum node intervals than the duck, usually more than fifty-five micrometers. On the other hand, duck has higher node density than the goose, more than sixteen per mm. Statistical analysis using the F-test showed that the maximum node interval and node density were useful characteristics for distinguishing a goose from a duck down.

著者

関口 和正 今泉 和彦 藤井 宏治 千住 弘明 水野 なつ子 坂井 活子 笠井 賢太郎 佐藤 元 瀬田 季茂

出版者

日本法科学技術学会

雑誌

日本鑑識科学技術学会誌 (ISSN:13428713)

巻号頁・発行日

vol.2, no.1, pp.33-40, 1997 (Released:2010-02-06)

参考文献数

29

被引用文献数

11 11

---

Nucleotide sequences of 2 hypervariable regions (HV1, HV2) within the control region of human mitochondrial DNA (mtDNA) were analyzed from 55 unrelated Japanese. About 700 nucleotides were sequenced by using the nested PCR and the solid-phase direct sequencing methods. Comparison of these sequences with Anderson's reference sequence revealed 97 mutation types within 93 positions, and 11 positions of them were novel. Fifty five samples analyzed were classified into 52 different sequences, while 3 pairs have shown the same sequences. Comparison of the Japanese sequences to those reported from other populations indicated many differences in such a point that the substitutions at 16,223 and 73 in Japanese were more frequent than those in Caucasian, while the substitutions at 16,126 and 16,311 in Japanese were less frequent than those in Caucasian. Twenty one of 55 samples analyzed showed a T-to-C transition at the position 16,189 of the C-stretch region in the HV1 region. This replacement caused the blurred bands on the sequence image, which resulted in the ambiguity of exact number of cytosine in the C-stretch region of HV1. For this ambiguity, the number of cytosine in the C-stretch region should not be currently taken into account in forensic practices of individualization of evidence samples. Regardless of such problem, the polymorphisms of HV1 and HV2 regions are highly useful for individual identification.