Reiko Kumagai

Determination of deleted regions from Yp11.2 of an amelogenin negative male

The use of short tandem repeat (STR) multiplexes with the incorporated gender marker amelogenin is now common practice in forensic laboratories. The amelogenin locus is encoded by two single copy genes located on Xp22.1-Xp22.3 (AMELX) and Yp11.2 (AMELY). There are differences in size and sequence between AMELX and AMELY that can be used for sex-typing tests. A sized-based difference for AMELX and AMELY is an integral part of most PCR multiplex kits that are used for DNA profiling. However, we experienced a case of a normal male being typed as female (dropout of the amelogenin Y allele) with AmpFlSTR Profiler kit, AmpFlSTR Identifiler kit and PowerPlex 16 System. Further testing with Y-STR loci using the AmpFlSTR Yfiler kit revealed an additional null at DYS458 locus in this amelogenin negative male. We examined the deleted regions using a total of 60 loci from Y-STRs, STSs (sequence tagged sites) and newly designed primer sets. Three deleted regions in Yp11.2 were seen in this sample. The sizes of these deletions were approximately 2.51 Mb, 25 kb and 834 b, respectively. The deletions did not belong to the five reported patterns in a collection of 45 deletion males from 12 populations described by Jobling et al.

Distribution of Aconitum alkaloids in autopsy cases of aconite poisoning

Aconite is a well-known toxic-plant containing Aconitum alkaloids such as aconitines, benzoylaconines, and aconins. We describe here the distribution of Aconitum alkaloids detected by liquid chromatography-tandem mass spectrometry (LC/MS/MS) in three autopsy cases of suicide by aconite poisoning. Case 1: a male in his fifties had eaten aconite leaves. The concentrations of jesaconitine in cardiac blood, urine, and kidney were 12.1 ng/ml, 993.0 ng/ml, and 114.2 ng/g, respectively. Case 2: a female in her fifties had eaten aconite root. The aconite root in the stomach included a high level of mesaconitine. The concentrations of mesaconitine in cardiac blood, liver, and kidney were 69.1 ng/ml, 960.9 ng/g, and 776.9 ng/g, respectively. Case 3: a male in his sixties had drunk liquor in which aconite root had been soaked. The concentrations of mesaconitine and aconitine in cardiac blood were 259.5 and 228.5 ng/ml, respectively. The Aconitum alkaloid levels were very high in the liver. The absorption of ethanol and Aconitum alkaloids might have been increased because of his having undergone total gastrectomy. In all three cases, the Aconitum alkaloid levels were high in the liver and kidney and low in the heart and cerebrum. The level in the cerebrum was lower than that in blood. Data on the distribution of the Aconitum alkaloids in the body in cases of aconite poisoning is useful to elucidate various actions of aconite alkaloids.

Distinct breakpoints in two cases with deletion in the Yp11.2 region in Japanese population

The amelogenin gene on the Y chromosome (AMELY) is a homolog of the X chromosome amelogenin gene (AMELX), and the marker is employed for sexing in forensic casework. Deletion of the sequences in the Yp11.2 region containing the AMELY locus has been found in males from various ethnic populations. Two cases of AMELY null males found in the Japanese population had different Y haplogroups and deletion mapping. Proximal and distal breakpoints of a sample of haplogroup D2* were located in TSPYA and TSPYB arrays, respectively, suggesting that the deletion mechanism was non-allelic homologous recombination (NAHR). On the other hand, a sample of haplogroup O3a3c* had the distal breakpoint in the TSPYB array and the proximal breakpoint at position 7.94 Mb, not in the TSPYA array. The likely deletion mechanism is non-homologous end-joining. High-resolution STS mapping in the TSPYB array showed the distal breakpoints differed according to the haplogroups. The deletion length was estimated as 3.1–3.7 Mb and 1.6–1.7 Mb for the sample of haplogroup D2* and O3a3c*, respectively. These deletion events should have occurred independently.

Application of quantitative ethanol detector (QED) test kit to measure ethanol concentration in blood samples.

In this paper, the applicability of the quantitative ethanol detector (QED) test kit for screening of ethanol concentrations in blood samples was investigated. The pretreatment of blood using the sulfosalicylic acid solution and the three-way stopcock followed by membrane filtration gave satisfactory results. The ethanol concentrations in whole blood samples (n=61) determined by QED correlated well with those determined by gas chromatography; the correlation coefficient indicated 0.990. Because a high correlation coefficient (0.928) was also confirmed in trial by investigators, QED test should be highly considered for ethanol screening in forensic praxis.

Human Inter-Alpha-Trypsin Inhibitor (ITI) Silent Allele Found in a Case of Disputed Paternity

Inter-alpha-trypsin inhibitor (ITI) is a 180-kDa glycoprotein having the role of a serine protease inhibitor. It has been revealed that ITI is not a single polypeptide chain structure, but a complex of three kinds of subunits, two heavy (H1 and H2) chains and a light (L) chain (Bourguignon et al. 1983) with chondroitin sulfate cross-links (Jessen et al. 1988). In situ hybridization showed that the H1, H2 and L chains were encoded by separate genes located on chromosomes 3, 10 and 9, respectively (Diarra-Mehrpour et al. 1989). Genetic variation of ITI on an isoelectric point was reported by Vogt and Cleve (1990) being controlled by mainly three alleles (ITI*1, ITI*2 and ITI*3) with autosomal codominant inheritance. The utility of ITI system has been supported from the results of several population studies (Luckenbach et al. 1991; Vogt et al. 1991a, 1991b; Yuasa et al. 1991; Vogt et al. 1992). However, Vogt et al. (1991b) indicated the cautious application of ITI for paternity testing due to an incomplete expression of ITI phenotypes among infants.