A validation study was performed on the new STR (Short tandem repeat) multiplex PCR Kit for human identification: AmpFℓSTR^® Identifiler^® Plus PCR Amplification Kit (IDPlus) released from Applied Biosystems. IDPlus contains the same fifteen loci as AmpFℓSTR^® Identifiler^® PCR Amplification Kit (ID) which is currently widely utilized in forensic DNA analysis. Consequently, IDPlus has the same discrimination ability as ID. According to the manufacturer, this kit has higher sensitivity, more resistant to PCR inhibitors and less background noise in electrophoresis. Thus, IDPlus was expected to be applied to forensic samples difficult to DNA profiling using ID. An applicability of IDPlus to forensic STR analysis was evaluated. Our study confirmed that IDPlus was more sensitive than ID. IDPlus has about 1.4 times to 1.5 times higher peak than ID when using the same PCR cycle number (28) for both kits. While ID has only one PCR protocol, IDPlus has two PCR protocols differing in cycle number: 28 and 29. To clarify the basic ability we compared heterozygous peak height ratio, stutter, intra-color balance, inter-locus balance among IDPlus to both protocols and ID from 94 individual DNA samples. Lower peak height ratio and the larger standard deviation in heterozygous samples were observed when using IDPlus 29-cycle compared to IDPlus 28-cycle. There was no significant difference between ID and IDPlus 28-cycle and between ID and IDPlus 29-cycle about the peak height ratio. Stutter ratios significantly were different in some loci between ID and IDPlus. Although Applied Biosystems supplies one stutter ratio to filter peaks for each locus to IDPlus in spite of having two PCR protocols, it was confirmed that the same stutter ratio could proper filter out stutter peaks for both cycle numbers. With regard to intra-color balance and inter-locus balance, IDPlus 28-cycle tended to be the highest in balance and ID tended to be the lowest in balance across all the samples and colors. Our validation study indicates IDPlus kit is useful in forensic applications, especially for analysis of trace DNA samples when using 29 cycles. However, forensic biologists must be cautious in interpreting DNA profiles obtained using IDPlus 29 cycles, because peak balance in heterozygous samples tended to be imbalanced when using 29 cycles compared to 28 and ID.

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  We compared automated DNA extraction instruments of AutoMate Express, EZ1 Advanced XL, Maxwell 16 and QIAcube for forensic purpose. DNA was extracted from fresh bloodstains and fresh diluted bloodstains on cotton and denim, three 3-mm punches of FTA card containing buccal cells collected by EasiCollect, and head hair roots and shafts. The genomic and mitochondrial DNA was quantified by real-time PCR assay using D17Z1 locus and/or the C region of hyper variable region 1 (HV1). The extracted DNA was used to amplify 15 STR loci of Identifiler kit and/or the A and the C regions in HV1.
  AutoMate Express tended to give the highest DNA concentration from all the samples except for FTA cards and hair roots. Full STR profiles were obtained using all the instruments from bloodstains on cotton and denim, FTA cards and hair roots. Out of the 15 diluted bloodstain samples on cotton and denim, full STR profiles were obtained from 14 and 15 samples for AutoMate Express, 11 and 14 samples for EZ1 Advanced XL, 0 and 6 samples for Maxwell 16, and 8 and 14 samples for QIAcube, respectively. When 20 μl of the denim extract was concentrated and amplified with 1 ng of 9947A DNA, PCR inhibition was slightly observed using AutoMate Express and Maxwell 16, but not observed when using EZ1 Advanced XL and QIAcube.
  When the A and the C regions of HV1 were amplified using 2,000 copies of the hair root DNA extracted by all the instruments, positive bands were observed from almost all the samples. On the other hand, when 2,000 copies or less of the hair shaft DNA were amplified, the bands of the A region were weaker than those of the C region for all the instruments especially for AutoMate Express.
  In conclusion, AutoMate Express and EZ1 Advanced XL are suitable for DNA extraction from forensic samples, since they are easier to operate than QIAcube is, and they give higher DNA yield than Maxwell 16 does.

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  A standard autoinjector (Shimadzu AOC-20i) was upgraded with a dedicated program and applied for the automatic operation of micro extraction by packed sorbent (MEPS) instead of an expensive multipurpose autosampler to carry out a confirmation analysis of methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine and 3,4-methylenedioxyamphetamine in hair by gas chromatography/mass spectrometry. Specification of the inlet liner, which is important for large volume injection utilizing programmable temperature vaporization (PTV), was studied, and lifetime of the liner was evaluated by repetitive analyses. By utilizing this system, full-scan electron-ionization mass spectra that were identical to the authentic acetylated analytes were observed using 3 mg of a fortified hair sample at 0.20 ng mg⁻¹, which was more sensitive than the previous system. Although the lifetime of the inlet liner was relatively short (12-13 times use), this system is beneficial for the confirmation analysis of amphetamine-type stimulants in hair.

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  We have attempted to establish the analytical condition of 17-ketosteroids (17-KS), i.e., androsterone (An), etiocholanolone (Eti) and dehydroepiandrosterone (DHEA) for identification of human urine with gas chromatography-mass spectrometry. First, we optimized the condition of acid-hydrolysis of 17-KS conjugates in human urine. Heating at 100°C for 20 min with 3% of HCl gave maximum yields of liberated 17-KS, and excess HCl and heating for a long period caused a degradation of An and DHEA. Subsequently, we attempted to apply the heptafluorobutyryl (HFB) derivatization method using an extraction solvent containing HFB-chloride. This method is convenient because 17-KS are derivatized and extracted simultaneously at room temperature. The highest recoveries were obtained when n-hexane containing 5% HFB-chloride and 0.1% triethylamine was used as the extraction solvent. Using this method, we successfully detected the 17-KS in mock forensic samples. We therefore suggest that this method is useful for the identification of human urine in forensic science.

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  Recently, many types of hair wigs have been widely used for hairdressing, hair restoring and medical use. Therefore, the hair materials from wigs can be recovered as physical evidence at crime scenes in addition to natural hairs of victims and suspects. As materials used for manufacturing wigs, in general, human scalp hair and artificial hair made from materials such as nylon, polyester and acrylic fiber have been used. In this study, we examined the cuticle morphology of wig hairs under a scanning electron microscope (SEM). The cuticles of human hair are removed by chemical treatment to reduce tangles. The surface of wig hairs after chemical treatment is smooth. In addition, if an unique cuticular trace lines along the hair axis can be observed on the hair surface, it will help to identify the hair wig manufacturing company. Material samples from wigs hereafter may be useful for forensic hair comparison.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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