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Determination of Oleandrin in Blood and Liver Samples by LC-MS/MS ZHAI Jin-xiao, YAN Hui, SHEN Min，et al. 2018, 34(6): 585-589.  DOI: 10.12116/j.issn.1004-5619.2018.06.002 Abstract ( 379 )   PDF (1403KB) ( 847 )   Objective To develop a liquid chromatography-tandem mass spectrometry （LC-MS/MS） analytical method for the determination of oleandrin in blood and liver tissues, which could be applied to the cases of death caused by oleander poisoning. Methods Blood or liver tissues underwent a liquid-liquid extraction （LLE） using ethyl acetate, and the extract was separated on an Agilent ZORBAX SB-C18 column and eluted with a gradient of acetonitrile and 20 mmol/L ammonium acetate （containing 0.1% formic acid）. Oleandrin was detected using electrospray positive ionization （ESI+） with multiple-reaction monitoring （MRM） mode. Results Oleandrin showed excellent linearity in both blood and liver samples in the corresponding linear range （r>0.995 0）, with detection limits 1 ng/mL and 2 ng/g, respectively, extraction recovery rates greater than 70.50%, both intra- and inter-day precisions less than 10.71%, accuracies 98.42%-111.63%, and matrix effects 91.52%-106.39%. The method was successfully applied to a case of suspected oleander poisoning. Oleandrin was detected in the blood, urine, liver tissues, bile, stomach wall tissues and stomach contents of the cadaver, with the content ranging from 65.5 to 29 600.0 ng/mL （ng/g）. Conclusion The method developed in this study is simple and convenient to operate with good selectivity, and is suitable for the analysis of oleandrin in biological samples such as blood and liver tissues, which can provide technical support for forensic identification and clinical diagnosis and treatment of oleander poisoning. Related Articles | Metrics

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Analysis of Common Herbicides in Blood by UPLC-HRMS YANG Yang, ZHANG Xiao-guang, YU Feng，et al . 2018, 34(6): 590-594，600.  DOI: 10.12116/j.issn.1004-5619.2018.06.003 Abstract ( 344 )   PDF (1637KB) ( 759 )   Objective To develop a method to screen and quantify 10 common herbicides （paraquat, diquat, glyphosate, glufosinate, cyanazine, atrazine, metazachlor, acetochlor, chlorsulfuron, and metsulfuron） in blood. Methods With acetonitrile-water solution [V（acetonitrile）∶V（water）=3∶1] as protein precipitant, 10 common herbicides in blood were detected using ultra-high performance liquid chromatography-high resolution mass spectrometry （UPLC-HRMS）. Results All the 10 herbicides had good linearity in their linear range （coefficient of determination R2≥0.993）, with the recovery rates 67.4%-111.9%, the relative standard deviations 1.5%-10.8%, the accuracies 85.1%-106.1%, intra-day precisions 2.7%-13.5%, and inter-day precisions 3.3%-13.3%. Conclusion This method is easy to operate with high recovery rates. It enables rapid and accurate qualitative screening and quantitative analysis of various herbicides in blood simultaneously. References | Related Articles | Metrics

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Retention Time of Four Common Poisons （Drugs） by GC-MS Qualitative Analysis LIU Shao-dan, MIN Tao, WANG Mei，et al. 2018, 34(6): 595-600.  DOI: 10.12116/j.issn.1004-5619.2018.06.004 Abstract ( 494 )   PDF (1414KB) ( 659 )   Objective To investigate the maximum allowable deviation of retention time （RT） or relative retention time （RRT） between the common poisons （drugs） and standard solvent by gas chromatography-mass spectrometry （GC-MS）. Methods After pretreatment with liquid-liquid extraction, four common poisons （drugs）—dichlorvos, phorate, diazepam and estazolam—were detected by full scan mode GC-MS. RT and RRT were analyzed according to combined uncertainty and expanded uncertainty. Results The expanded uncertainty of RT and RRT were 6.0×10-4-14.1×10-3 and 2.5×10-6-5.9×10-5 （k=3）, respectively. The RT of poisons （drugs） was relatively stable in blood samples with different mass concentrations. Among dichlorvos, phorate, diazepam and estazolam, the absolute deviation and relative deviation of RT were ≤0.03 min and ≤0.4%, respectively, and those of RRT were ≤0.003 min and ≤0.3%, respectively. Conclusion The maximum allowable deviations of RT and RRT for common poisons （drugs） in blood samples are recommended to be ±0.05 min and ±0.5%. Related Articles | Metrics

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Decomposition Kinetics of Omethoate in Blood LI Peng, WANG Hao-yu, BI Wen-ji,et al. 2018, 34(6): 601-605，610.  DOI: 10.12116/j.issn.1004-5619.2018.06.005 Abstract ( 224 )   PDF (1273KB) ( 615 )   Objective To study the decomposition kinetics of omethoate in blood. Methods The acetonitrile precipitated protein was added into the blood, with the chromatographic column of a Waters BEH C18 column （2.1 mm×50 mm, 1.7 μm）, the mobile phase of 5 mmol/L ammonium acetate aqueous solution-methanol, and the gradient elution with a flow rate of 0.3 mL/min and injection volume of 2 μL. With electrospray ionization （ESI） source and positive ion detection, qualitative and quantitative analyses were taken using multi-reaction monitoring mode. Omethoate standard was added into blank human blood to the mass concentrations of 0.78, 1.40, 2.30, 4.50, and 7.20 μg/mL, and each mass concentration was preserved at 3 temperatures of -20 ℃, 4 ℃, and 20 ℃, respectively. The content of omethoate was detected at different time points （0, 1, 3, 4, 7, 11, 15, 24, 32, 40, 48, 64, 80, 96, and 120 d）. Results Different concentrations of omethoate all showed a descended trend in human blood under different temperature conditions. The decomposition in storage environment of -20 ℃, 4 ℃, and 20 ℃ was fit to a one-compartment open model with a first-order kinetic process, which could be expressed as Ct=Coe-αt, with the calculated theoretical values of omethoate concentration close to the measured values. Conclusion All concentrations of omethoate are decomposed in the blood, which vary a lot in different preservation conditions. It is suggested that blood samples should be frozen and detected timely in suspected omethoate poisoning cases. References | Related Articles | Metrics

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Qualitative and Quantitative Analysis of Cathinones in Human Urine by SPE-GC-MS WANG Ping, LIU Xiao-yun, LIU Yao，et al 2018, 34(6): 606-610.  DOI: 10.12116/j.issn.1004-5619.2018.06.006 Abstract ( 257 )   PDF (1044KB) ( 762 )   Objective To propose an alternative solid phase extraction-gas chromatography-mass spectrometry （SPE-GC-MS） method for the sensitive determination of cathinones in human urine samples, plus methodological verification. Methods Human urine samples were concentrated by solid phase extraction （SPE） sorbent and converted into the corresponding heptafluorobutyric acid anhydride derivatives. Methcathinone, 4-methyl methcathinone and 3,4-methylenedioxy-N-methylcathinone were detected by gas chromatography-mass spectrometry （GC-MS）. With quantitative analysis by internal standard method, methodological verification was carried out from the aspects of specificity, precision and reco-very rate. Results Methcathinone, 4-methyl methcathinone and 3,4-methylenedioxy-N-methylcathinone showed good linearly in the range of 25-200 ng/mL of urine （r>0.99）, with the limits of detection 2.0 ng/mL, limit of quantitation 25.0 ng/mL, both intra- and inter-day coefficients of variation lower than 6.0%, and recovery rates of 98.4%-105.7%. Conclusion The proposed SPE-GC-MS procedure has good accuracy and specificity, can meet the need of qualitative and quantitative analysis of cathinones in the urine of drug abusers, and  therefore provide technical support for the detection of cathinone abuse. Related Articles | Metrics

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Research Status of New Designer Drug Methcathinone in Forensic Toxicology DENG Yan-fei, LIU Liang, YANG Zhi-xi，et al. 2018, 34(6): 611-616.  DOI: 10.12116/j.issn.1004-5619.2018.06.007 Abstract ( 292 )   PDF (973KB) ( 807 )   Methcathinone, a new cathinone designer drug, which is structurally similar to amphetamine analogs, is a central nervous stimulant. Recently, there has been a worldwide rise in its popularity and abuse, and a growing number of cases with disability or even death is reported in several countries, resulting in public concern. The typical symptoms include accelerated heartbeat, high temperature, anxiety, depression, etc. Forensic studies on its toxicity mechanism are rare. This article reviews its toxicological effects, poisoning symptoms, poisoning and addiction mechanisms, and detection methods, to provide theoretical reference for future studies and guidance for related forensic identification. Related Articles | Metrics

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Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms#br# DONG He-wen, LI Wei, LI Shi-ying，et al. 2018, 34(6): 619-624.  DOI: 10.12116/j.issn.1004-5619.2018.06.009 Abstract ( 180 )   PDF (4250KB) ( 645 )   Objective To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy （FTIR-MSP） combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages. Methods Electrical skin injury model was established on swines. The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control. Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired. With the combination of machine learning algorithms such as principal component analysis （PCA） and partial least squares-discriminant analysis （PLS-DA）, different spectral bands were selected （full band 4 000-1 000 cm-1 and sub-bands 4 000-3 600 cm-1, 3 600-2 800 cm-1, 2 800-1 800 cm-1, and 1 800-1 000 cm-1）, and various pretreatment methods were used such as orthogonal signal correction （OSC）, standard normal variables （SNV）, multivariate scatter correction （MSC）, normalization, and smoothing. Thus, the model was optimized, and the classification effects were compared. Results Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups. PLS-DA based on the 3 600-2 800 cm-1 band was used to identify the different voltages induced skin injuries. The OSC could further optimize the robustness of the 3 600-2 800 cm-1 band model. Conclusion It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms. Related Articles | Metrics

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Liver Tissue-related Metabolic Mechanism of Different Infusion Volumes for Hemorrhagic Shock LI Meng-ni, HU Zhi-mei, PANG Yuan，et al. 2018, 34(6): 625-630，634.  DOI: 10.12116/j.issn.1004-5619.2018.06.010 Abstract ( 161 )   PDF (6726KB) ( 581 )   Objective To investigate the curative effects of various infusion volumes on liver-related metabolic mechanism in the treatment of hemorrhagic shock. Methods A severe hemorrhagic shock rabbit model was established in 30 rabbits. The rabbits were randomly divided into three groups： non-infusion group （A）, conventional infusion group （B）, and excessive infusion group （C） （n=10 in each group）. Taking group B as the control, groups A and C were observed for the damage of non-infusion and excessive infusion, respectively. The outcomes in the three groups and their relations with liver tissue metabolism changes were analyzed with gas chromatograph-mass spectrometer （GC-MS）. Results The mortality in groups A, B, and C group were 80%, 0%, and 70%, respectively. The liver tissue metabolic profile in group B showed statistically significant difference compared with that in groups A and B. In group C, the levels of 21 metabolites were lower than those in group B, and the levels of 8 metabolites were lower than those in group A. The relative contents of various metabolites were correlated with infusion volumes, and the succinic acid content was associated with death events （P<0.05）. Conclusion The conventional infusion has significant curative effect on hemorrhagic shock. The metabolites of liver tissues with excessive infusion are generally decompensated and have longer survival time than those in non-infusion group, which may caused by the excessive infusion-induced blood volume increase after hemorrhagic shock. Tissue fluid dilution is an important cause of death. References | Related Articles | Metrics

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Pathological Changes of Petechial Hemorrhage after High Temperature Treatment CHEN Qing, CHEN Chang-can, BAI Jie 2018, 34(6): 631-634.  DOI: 10.12116/j.issn.1004-5619.2018.06.011 Abstract ( 171 )   PDF (3675KB) ( 583 )   Objective To study the main features of mechanical asphyxia--the pathological characteristics of petechial hemorrhage after high temperature effect （roasted, boiled） and its changing rules. Methods Rabbit model of mechanical asphyxia death with choking neck and death from anteposition hanging was established. The experimental rabbits were randomly divided into roasted group and boiled group （n=4, in each group）. The laryngeal ventricles and cardiopulmonary tissues in the roasted group were roasted for 3, 6 and 10 min, and the positions of petechial hemorrhage were observed and photographed. The same organs and tissues in the boiled group were heated in boiling water （100 ℃）, and were observed and photographed at 30 and 60 s. Then histopathological examination was performed on all the laryngeal ventricles and cardiopulmonary tissues. Results The petechial hemorrhage originating from laryngeal ventricle, trachea and lung did not disappear after high temperature treatment in the eight rabbits. The deepened color was visible to naked eyes and distinct from the surrounding normal tissues, with bleeding under the microscope. Conclusion Petechial hemorrhage caused by mechanical asphyxia would not disappear under high temperature, which might be related to the manner of death, the intensity and time of action, and the individual differences. Related Articles | Metrics

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Optic Nerve Crush Induces Changes of Hydrogen Sulfide Synthases Expression in the Rat Retina ZENG Ming-wei, WANG Tao, FEI Cheng-ping，et al. 2018, 34(6): 635-639.  DOI: 10.12116/j.issn.1004-5619.2018.06.012 Abstract ( 194 )   PDF (4141KB) ( 621 )   Objective To investigate the expression changes of the hydrogen sulfide synthases cystathionine γ-lyase （CSE）, cystathionine β-synthase （CBS）, and 3-mercaptopyruvate sulfurtransferase （3-MST）, after optic nerve crush （ONC） in rat the retina. Methods The rat model of ONC was established. Rats were divided into normal control, ONC, and sham control groups. Histopathologic changes in retina, the number of retinal ganglion cells （RGC） and retinal thickness of inner part （RTIP） were measured. The changes of CSE, CBS and 3-MST mRNA expression were detected with quantitative real-time PCR. Results The retinal histostructure was normal in normal controls and with minor changes in sham controls, respectively. Compared with sham group, significant retina damages were found in the ONC group： a time-dependent reduction of RGC number and RTIP. Expressions of CSE, CBS and 3-MST mRNA in rat retina were detected in normal control. Compared with normal controls, the expressions of CSE, CBS and 3-MST mRNA did not show any significant changes in the sham controls. Compared with sham controls, CBS mRNA expressions showed a time-dependent increase at 3 d, 7 d and 14 d after crush in the ONC group; CSE mRNA expressions increased to the peak at 3 d and then slightly reduced at 14 d after crush; 3-MST mRNA expressions showed the trend of increase at 3 d and 7 d and then enhanced remarkably at 14 d after crush. Conclusion Hydrogen sulfide synthases CSE, CBS and 3-MST expressions were up-regulated in rat retina following ONC, which may cause an increase in local endogenous hydrogen sulfide production in the retina and a compensatory protective effect. Related Articles | Metrics

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Analysis of Late Positive Component of Event-related Potentials by Face Expression Images in Traumatic Brain Injury Patients with Mood Disorders DONG Ri-xia, DU Xiang-dong, YANG Jian-gong，et al. 2018, 34(6): 640-643.  DOI: 10.12116/j.issn.1004-5619.2018.06.013 Abstract ( 220 )   PDF (1219KB) ( 614 )   Objective To explore the application of event-related potentials （ERP） by positive, negative, and neutral face expression images in the evaluation of mood disorders in brain traumatic patients. Methods ERP was tested by face expression images in 24 patients mainly with anxiety and depression symptoms （depression group） and 19 patients mainly with hostile and suspicion symptoms （hostile group）, respectively. The findings were compared with those of the control group. Results There were no significant differences, between the depression group and the hostile group, on latencies and amplitudes of late positive potential （LPP） induced by the three types of face expression images, except the amplitude induced by negative face expression image. Compared with the control group, the latencies were extended and the amplitudes were lower in both depression and hostile groups. Within each group, the difference of latencies induced by the three images was not significant. The amplitudes induced by negative face expression image was higher than those induced by positive and neutral face expression images, with significant differences in the hostile group and the control group （P<0.05） but not in the depression group. Conclusion Changes in latencies and amplitudes of LPP could be an objective indicator in the evaluation of mood disorders of brain traumatic patients. The LPP induced by negative face expression images could be more meaningful for patients mainly with anxiety and depression symptoms. Related Articles | Metrics

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Forensic Analysis of 24 Cases of Long-term Antipsychotics Use-Induced Sudden Unexpected Deaths#br# YE Xing, SHI Cheng, SHEN Yi-wen，et al. 2018, 34(6): 644-647.  DOI: 10.12116/j.issn.1004-5619.2018.06.014 Abstract ( 405 )   PDF (1063KB) ( 816 )   Objective To analyze the forensic characteristics of 24 psychiatric patients who died of long-term use of psychotropic drugs. Methods Cases of sudden death of psychiatric patients from 2011 to 2016 were collected. The forensic characteristics of these sudden deaths were retrospectively analyzed by systematic investigation plus results of autopsy and toxics （drugs）. Results Among the 24 psychiatric patients who died of long-term use of psychotropic substances, the ratio of male to female was 1.7∶1, and the average age was （59.0±8.8） years. Fifteen patients had clear disease durations （14.4±8.2） years, and other the nine were known to have disease durations of over 3 years. The death time of 62.5% of patients was the daytime in working days, and 91.7% of the patients died at home. Most patients complained different degrees of physical discomfort before death. Patients with schizophrenia （20 cases） were the most common, followed by depression （4 cases）. All patients had the history of taking psychotropic drugs, with clozapine and chlorpromazine being the mostly detected ones. The causes of death were mainly circulatory diseases （15 cases）, with the most common being myocarditis （11 cases） followed by pneumonia （4 cases）. Conclusion Critical attention should be paid to the risk of antipsychotics-induced sudden unexpected deaths for psychiatric patients, particularly for those with schizophrenia. Related Articles | Metrics

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Analysis of 13 Cases of Abnormal Death after Drinking WANG Cheng-yi, YANG Li-ping 2018, 34(6): 648-649.  DOI: 10.12116/j.issn.1004-5619.2018.06.015 Abstract ( 360 )   PDF (1038KB) ( 866 )   Objective To investigate the common causes of death after drinking and the precautions for forensic identification. Methods By reading alarm records, visiting investigations, on-site investigation transcripts, medical examination records and identification documents, the sex, age, corpse examination, toxic （drug） analysis and cause of death in 13 cases of post-drinking death were retrospectively analyzed. Results In 13 cases of post-drinking abnormal death, the causes of death were mainly drowning after drinking and asphyxia induced by stomach contents reflux. However, when accompanied by injury or other toxic poisoning, competition of death causes often occured. Conclusion Combining the case and on-site inspection, a comprehensive systematic corpse examination and toxic （drug） analysis is of great significance for the forensic identification of cadavers of non-acute ethanol poisoning after drinking. Related Articles | Metrics

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Analysis of Genetic Polymorphism and Genetic Distance of 19 Autosomal STR Loci in Jiangsu Han Population PAN Meng, CUI He, JU Xiao-bin，et al. 2018, 34(6): 650-655.  DOI: 10.12116/j.issn.1004-5619.2018.06.016 Abstract ( 263 )   PDF (1169KB) ( 680 )   Objective To investigate the distribution of alleles in 19 autosomal short tandem repeat （STR） loci in Jiangsu Han population. Methods Goldeneye?? 20A kit was used to detect 9 025 samples. Genetic analysis was performed on typing data of 19 autosomal STR loci, and genetic distance with other 17 populations was analyzed. Results All the 19 autosomal STR loci were consistent with the Hardy-Weinberg equilibrium （P>0.05）, with the heterozygosity 0.616 1-0.916 3, probability of match 0.012 8-0.202 6, discrimination power 0.797 4-0.987 2, probability of paternity exclusion 0.310 8-0.828 8, and polymorphic information content 0.561 7-0.913 6. The cumulative discrimination power and cumulative probability of exclusion were 0.999 999 999 999 999 998 434 1 and 0.999 999 989, respectively. The Jiangsu Han population had close genetic distances with the Han population in Tianjin, Hunan and Jilin, and significant difference with Han population in Aletai region in Xinjiang （P<0.05）. Conclusion The STR allele polymorphism data and population genetic parameters of Jiangsu Han population can provide data support for the forensic application of these STR loci in Jiangsu Han population. Related Articles | Metrics

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Quantification and Genotyping of Trace Samples SONG Li, LIU Song, WU Hui，et al. 2018, 34(6): 656-658.  DOI: 10.12116/j.issn.1004-5619.2018.06.017 Abstract ( 209 )   PDF (1082KB) ( 594 )   Objective To introduce real-time polymerase chain reaction （real-time PCR） into the initial sample screening, to improve the effectiveness of traditional trace sample extraction method. Methods Serial diluted 9947A was quantified using a Rotor-Gene Q real-time RT-PCR, and the genotype was determined with AmpF?STRTM IdentifilerTM Plus PCR kit. Thus a quantitative threshold model was built to obtain complete STR typing from the trace samples. In addition, 903 trace samples were used to verify the reliability. Results When the samples quality concentration was >0.03 ng/μL, the effective STR typing could be directly obtained; when the concentration was >0.01 and ≤0.03 ng/μL, the effective STR typing could be directly obtained by optimizing the PCR thermal cycle parameters （30 cycles）; and when the concentration was ≤0.01 ng/μL, no effective map could be obtained even if PCR was optimized. Conclusion The real-time PCR quantitative threshold model is effective for the screening of trace samples.forensic genetics; tandem repeat Related Articles | Metrics

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Behavioral Characteristics and Medicolegal Identification of Infanticide DING Yang, LU Qin, WANG Chun-guo,et al. 2018, 34(6): 659-664.  DOI: 10.12116/j.issn.1004-5619.2018.06.018 Abstract ( 614 )   PDF (1128KB) ( 1257 )   Due to the concealment and incidence higher than reported statistics, infanticide should attract the attention of legal medical experts. The infanticide process has common behavioral characteristics. The perpetrators are most frequently biological mothers who are unmarried, with inferior education, and lack of routine pregnancy tests. Medicolegal identification of infanticide cases includes identification of live births and causes of death. Besides the classical lung floating test, there are other methods to identify live births such as pulmonary interstitial emphysema, CT imaging examination, immunohistochemical examination of umbilical cord vitality markers. Neonatal line measurement is the only way to identify live births in corpse with severe decomposition. The main causes of death in infanticide are mechanic asphyxia and fatal head trauma. Shaken baby syndrome, as a common abusive head trauma, is pathologically characterized by the triad of encephalopathy, subdural haemorrhage （SDH） and retinal haemorrhage （RH）. During the autopsy of suspected shaking baby syndrome, in addition to carefully examining cervical cord, the possibility of pathological temporal lobe hemorrhage should also be ruled out. Related Articles | Metrics

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Progress on the Muscle Function Evaluation and Its Forensic Application ZHUO Pei-pei, GAO Dong, RAN Dan,et al. 2018, 34(6): 665-671.  DOI: 10.12116/j.issn.1004-5619.2018.06.019 Abstract ( 260 )   PDF (1108KB) ( 769 )   Accurate evaluation of muscle function helps to understand the recovery of muscle, bone, nervous system diseases or injuries, especially for muscle dysfunction caused by peripheral nerve injury. Therefore, the methods of muscle function evaluation have been the focus of researchers, with new methods having been constantly proposed. Muscle strength testing is an important part of muscle function evaluation. Besides hand muscle strength assessment, currently used muscle function assessments include simple instrumental test, isokinetic muscle test, electrophysiological test, etc. In addition, the application of needle electromyography, motor unit number estimation, motion unit index in muscle function evaluation has also been reported for several times. This paper reviews the research progress and practical application of these methods. Related Articles | Metrics

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Research Progress on Discrimination of Monozygotic Twins XU Qian-nan, LI Cheng-tao, LIU Xi-ling 2018, 34(6): 672-677.  DOI: 10.12116/j.issn.1004-5619.2018.06.020 Abstract ( 459 )   PDF (1092KB) ( 936 )   Individual identification plays an import role in the practice of forensic medicine, and often provides crucial evidence for the analysis and detection of criminal cases. However, for individual identification in complex situations, such as monozygotic （MZ） twins assumed to be genetically identical, it is impossible to distinguish one from the other by using traditional forensic DNA typing system. Therefore, how to discriminate the MZ twins has become and will continue to be one of the difficult problems in forensic field. This paper summarized the genetic and epigenetic changes recently identified in MZ pairs, which might provide a new insight to forensic discrimination of MZ twins. Related Articles | Metrics