Sadao Yamada

Analysis of the STR loci HUMF13A01, HUMFXIIIB, HUMLIPOL, HUMTH01, HUMTPOX and HUMVWFA31 in a Japanese population

Population studies on six short tandem repeat loci, HUMF13A01, HUMFXIIIB, HUMLIPOL, HUMTH01, HUMTPOX and HUMVWFA31 were carried out in a sample of unrelated Japanese individuals (n = 337–545) living in Gifu Prefecture (central region of Japan). Five alleles could be identified for HUMFXIIIB, six for HUMF13A01, HUMLIPOL, HUMTH01 and HUMTPOX, and eight for HUMVWFA31. For all/six loci no deviations from the Hardy-Weinberg equilibrium hypothesis were detected. The mean exclusion chance ranged from 0.22 to 0.60, the power of discrimination from 0.63 to 0.93, and the expected heterozygosity from 0.43 to 0.80. Allele frequency distributions for the loci in the Japanese sample were not similar to those in samples from other racial or ethnic groups except for the Chinese (for HUMTPOX). The results demonstrate that HUMTH01, HUMTPOX and HUMVWFA31 are more useful for forensic investigations in the Japanese population than the other three loci.

DNA typing from cigarette butts

We performed DNA typing for D1S80, HLADQA1, TH01 and PM using the butts of 100 cigarettes that were smoked by ten different individuals (ten cigarettes per individual). The results obtained from DNA typing for D1S80 agreed with the results obtained using bloodstains in 76 cigarette butt samples. Sixteen samples produced false results, showing the loss of the longer allelic hetero-band. When examined using agarose gel electrophoresis, high-molecular weight DNA was not observed in these samples. The same results were also observed for buccal swab samples and saliva stains obtained from the same individuals. In the remaining eight cigarette butt samples, PCR products were not detected. The results obtained from DNA typing for TH01, HLADQA1 and PM agreed with the results obtained using bloodstains in 90 samples. In the remaining ten samples of a specific kind of cigarette (Marlboro), the PCR products were not detected. The extracts from the ends of the Marlboro cigarettes were stained yellow. When the DNA extracted from Marlboro cigarette butts was treated with Microcon-100 (amicon) or SizeSep 400 Span Columns (Amersham Pharmacia Biotech), PCR products could be detected. When PCR amplification was performed after adding extracts from the ends of unsmoked Marlboro cigarettes to DNA extracted from bloodstains, PCR products could not be detected. The present data indicate that the degradation of high-molecular weight DNA and the inhibition of PCR by dyes of the cigarette end should be kept in mind when performing DNA typing using cigarette ends.

Analysis of the VNTR locus D1S80 in a Japanese population

SummaryA population study on the VNTR locus D1S80 was carried out in a sample of 377 unrelated Japanese individuals living in and around Gifu Prefecture (central region of Japan). A total of 29 different alleles was distinguished. Alleles 18, 24 and 30 were found to be the 3 most common alleles in this population sample and their frequencies were 0.147, 0.200 and 0.162, respectively. Out of the 435 possible phenotypes, 120 were observed. The observed heterozygosity was 0.88 and the power of discrimination was 0.98. No significant deviations from Hardy-Weinberg equilibrium could be found in this Japanese population sample.ZusammenfassungEine populationsgenetische Studie über den VNTR Locus D1S80 wurde an einer Stichprobe von 377 unverwandten Japanern durchgeführt, welche innerhalb und in der Umgebung der Gifu-Präfektur (ZentralJapan) leben. Insgesamt wurden 29 verschiedene Allele unterschieden. Die Allele 18, 24 und 30 waren die 3 häufigsten Allele in dieser Populationsstichprobe, und ihre Frequenzen waren 0,147, 0,200 und 0,162. Von insgesamt 435 möglichen Phänotypen wurden 120 beobachtet. Die beobachtete Heterozygotie-Rate war 0,88 und der Diskriminations-Index betrug 0,98. In der untersuchten japanischen Stichprobe wurden keine signifikanten Abweichungen vom Hardy-Weinberg-Gleichgewicht gefunden. lated Japanse individuals living in and around Gifu Prefecture (central region of Japan).

Japanese Population DNA Typing Data for the Loci LDLR, GYPA, HBGG, D7S8, and GC

Population studies on the five loci LDLR, GYPA, HBGG, D7S8, and GC (PM loci) were carried out in a sample of 366 unrelated Japanese individuals living in Gifu Prefecture (central region of Japan) using the AmpliType PM PCR Amplification and Typing kit (Perkin Elmer). For all loci, no significant deviations from Hardy-Weinberg equilibrium could be found in our Japanese population sample. The combined mean exclusion chance and power of discrimination for the PM loci were 0.68 and 0.993, respectively. The Japanese and Chinese population data were similar for the all loci. The Japanese and Korean population data were similar for all loci other than D7S8. Significant differences were observed between the Japanese population data and the 16 other population data compared for 3 loci or more.

Origin of DNA in human serum and usefulness of serum as a material for DNA typing.

The aims of this study were to clarify the origin of DNA in human serum and to investigate whether serum is a material available for DNA typing in routine forensic practice. Blood was donated from 10 healthy adult volunteers and stored for up to 8 days, at 4 degrees C and at room temperature. The serum DNA concentration at zero time was in the range of 5.6 to 21.8 ng/ml with a mean of 12.2+/-1.6 ng/ml. The concentrations increased with storage time. On agarose gel electrophoresis, all serum samples showed ladder patterns and the size of each band was an integer multiple of approximately 180 bp considered to be characteristic of apoptosis. DNA typing from DNA released by apoptosis was possible. Exact DNA typing of D1S80, HLA DQA1, PM, CSF1PO, TPOX, TH01 and vWA was possible for each sample. These results indicate that serum contains fragmented DNA derived from apoptosis of leukocytes, especially neutrophils, and that fragmented DNA is an appropriate material for DNA typing.

AN UNUSUAL CASE OF FATAL GAS EMBOLISM

We describe an unusual case of fatal gas embolism, in which a man died by connecting an extension tube supplying oxygen to an indwelling catheter that was inserted into the left cephalic vein.

Vomit identification by a pepsin assay using a fibrin blue-agarose gel plate

Reported is a simple and reliable method for identifying the presence of gastric fluid in forensic samples by an assay that reveals the pepsin activity. These samples are usually vomit found at the scene of a crime, either in fresh form or as a dried stain on clothing. The pepsin within the sample is assayed for its proteolytic activity which is revealed in a fibrin blue-agarose gel plate, as a result of an enzymatic reactivity that takes the form of a concentric, blue, translucent ring around the tested sample. Apart from being able to determine the pepsin content of fresh or recent forensic samples, this method has also achieved positive reactions in aged gastric fluid stains that were kept at room temperature. No body fluids other than the gastric fluid and no proteolytic enzymes other than pepsin show a positive reaction with the use of this method. This method has an additional advantage, in that the enzymatic activity seen on the gel plate can be photographed and the gel plate, on drying, can also be preserved as evidence.

The STR locus D11S554: allele frequencies and sequence data in a Japanese population

Abstract A population study on the short tandem repeat (STR) locus D11S554 was carried out in a sample of 362 unrelated Japanese individuals living in the Gifu Prefecture. A total of 46 different alleles ranging from 180 bp to 340 bp and 135 genotypes were revealed. Sequence analysis of alleles was carried out for 185 samples. The sequence structures of the repeat regions of the alleles were found to be complex and the alleles were classified into nine sequence types, including four new sequence types. According to the system of Adams et al. (1993), we designated the new sequence types IA3, IA4, IA5 and IB3, respectively. Out of the 46 different alleles, 11 showed sequence heterogeneity. The results of this study demonstrated that the D11S554 locus is a powerful and useful genetic marker for forensic practice in the Japanese population.

Blood grouping of mixed bloodstains using immunocytochemical methods.

Immunocytochemical methods to determine the ABO blood group of each blood of mixed bloodstains have been developed. Mixed bloodstains were made on surgical blades and a cedar board. The blades were dipped into blood and then dipped into blood of a different group at intervals of 30, 20, 15, 10 and 5 s. Two drops of blood were dropped on a cedar board and then two drops of blood of a different group were dropped there at the same intervals. The bloodstains were dried for a week. The blood samples were removed from the blades or the cedar board and processed according with a routine histological method. Three serial thin sections were obtained. After deparaffinization, the sections were treated in papain solution for 2 h at 36 degrees C, to unmask antigenic sites on red cell membranes. The labeled streptavidin-biotin (LSAB) and peroxidase-anti-peroxidase (PAP) methods were used to detect A and B antigens, and an indirect immunocytochemical method for H antigen. These immunocytochemical methods showed specific immunologic reactions and allowed determination of the blood group of each blood of mixed bloodstains. Further, these methods indicated a possibility to determine who was stabbed first, in cases where two or more victims were stabbed with a single knife.