A repository of 14 PCR-loci Italian gene frequencies in the World Wide Web

A collection of 6830 typing results produced by the Immunohematology Laboratory at the UCSC, pertaining to 11 STRs (FES/FPS, vWA31, HUMTH01, F13A1, MBP, D21S11, D7S460, D18S51, CD4, TPOX, CSF1PO) and 3 AmpFLPs (D1S80, APO-B, COL2A1), is publicly available as an electronic archive at a website.     

Burn injuries caused by a hair-dryer--an unusual case of child abuse

About 1.4-26% burn injuries in children appear to be abusive in origin. A 2.5-year-old girl was referred to our institute because of suspected child abuse. Clinical examination and later interrogation of the mother revealed non-recent deep second degree burn injuries on both gluteal regions, caused by the partner of the mother by pressing a hand-held hair-dryer against the skin. The authors present the findings of this unusual method of child abuse.     

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fatal poisoning

To evaluate the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in fatal poisoning in relation to the effects of drugs and poisons on respiratory function, 42 forensic autopsy cases were examined by scoring the staining intensity. The highest scores of SP-A staining, with dense granular deposits (aggregates) in the intra-alveolar space, were observed in fatalities from pancuronium bromide (muscle relaxant) injection and petroleum (butane) gas inhalation. Poisoning with organophosphate pesticides and arsenic (ingestion) showed a second grade SP-A score. However, The SP-A scores were relatively low in ethanol and sedative-hypnotic intoxication. Carbon monoxide intoxication showed a varied degree of SP-A score, and the aggregated SP-A score tended to be higher in cases of lower blood carboxyhemoglobin concentration. A varied SP-A score was also observed in methamphetamine fatalities, in which the score was relatively low in cases with a higher serum drug level. Increase of SP-A was not always associated with the intra-alveolar effusion or hemorrhages. The above-described observations suggested that the immunohistochemical score of SP-A may be a possible indication for intensity and duration of drug/poison-dependent respiratory distress.     

A biomechanical reconstruction of a wound caused by a glass shard--a case report

During the course of a criminal trial, an investigating pathologist is commonly asked how much force was required to produce an injury. This subjective opinion is based on the pathologist's previous experience of dealing with wounds inflicted with similar weapons. However, in the case of stab wounds inflicted by broken glass, it is unlikely that two glass fragments would be physically similar. In the case studied, two theories were examined: that a wound resulted from a thrown glass fragment or that it had been caused as a stab injury by the glass held in the bare hand. The investigation involved quantifying the energy required for human tissue penetration, comparison of sharpness, a biomechanical analysis of throwing actions and testing of the hypothesis that if the glass shard were used as a stabbing implement it would result in a cut to the hand.The investigation utilised a scientific methodology that reduced the need for speculative (though informed) opinion from the pathologist by producing quantitative results.     

Postmortem biochemical examination of synovial fluid--a preliminary study

Vitreous humor chemistry is used for postmortem analysis since serum values of many components are thought to be reflected in vitreous humor and to be stable for a prolonged postmortem interval (pmi). A similar isolated compartment to vitreous humor is synovial fluid which up to now was hardly used for postmortem chemistry.The aim of the present examination was to compare the values of various analytes in both fluid compartments to get first hints for the reliability of the examination of synovial fluid. Therefore, in 74 cases of sudden death both fluids were taken and analysed for natrium, potassium, calcium, chloride, urea, creatinine, and glucose. The results show that the examination of synovial fluid as compared to vitreous humor is a reliable method to get hints on the premortal metabolic status since most analytes are stable postmortem. The range of all values is comparable in both fluids. The time course of glucose concentrations and, much more important, potassium concentrations is nearly similar. If no vitreous humor is available synovial fluid may be used with all precautions in diagnosis known from vitreous humor.     

Female homicide offenders have greatly increased mortality from unnatural deaths

The mortality of female homicidal offenders has scarcely been studied. Our aim was to examine the mortality of homicidal women in Finland using a representative nation-wide material. The data consisted of all 132 women who underwent forensic psychiatric examinations after committing homicide or attempted homicide in 1982-1992. We analysed their rate and cause of death during follow-up using standardised mortality ratios (SMRs) and the official classification of death. The mean follow-up time for dead subjects was 7 years (S.D. 4), and for the rest 11 years (S.D. 3). There were 22 observed deaths, the expected value being 1.3 (SMR 17.4). The SMR for unnatural deaths was 226 and for suicides 425. The SMRs for women below 40 years were over 220. In conclusion, homicidal women have an over 200-fold risk of unnatural death, rising to over 400-fold for suicide. This should be taken into consideration in planning discharge programmes for homicidal offenders.     

The forensic DNA implications of genetic differentiation between endogamous communities

In many indigenous minority populations, and among migrants from Asian and African populations now resident in western Europe, North America and Australia, there is a strong tradition of endogamy and a preference for consanguineous unions. These marriage practices can result in F(ST) values greatly in excess of the maximum value (0.01) currently recommended for forensic DNA purposes under guidelines established by the National Research Council (NRC) of the USA. To examine the possible extent of deviation from this accepted norm, three co-resident Pakistani communities were studied using 10 autosomal dinucleotide markers and six tetranucleotide markers on the Y-chromosome. The mean population subdivision coefficient (FST) value was 0.13 for the autosomal loci, and Y-chromosome loci exhibited even stronger differentiation with unique alleles identified in all three communities. The data indicate that even when sub-populations are virtually indistinguishable in terms of anthropology, geography, ethnicity or culture, they may still exhibit major genetic differentiation. Where significant population stratification is known to exist, more detailed genetic databases should be developed for forensic DNA purposes, based on reference data from each of the appropriate sub-populations and not on random or combined samples.     

Prevalence of rhabdomyolysis in drug deaths

Rhabdomyolysis has repeatedly been reported as a possible consequence of illicit drug consumption especially in clinical literature. In order to investigate the prevalence of rhabdomyolysis in cases of drug deaths, immunohistochemical staining of kidney sections with a myoglobin antibody was performed at 103 consecutive fatal drug poisonings. The control group consisted of 107 unselected forensic autopsies. With regard to the presence of intratubular myoglobin, 33% of the study group were categorized as "strongly positive", 17.5% as "slightly positive" and 49.5% as "negative". No single substance showed a particularly high incidence of rhabdomyolysis nor were there correlations to special combinations of substances. In the control group a "strongly positive" result after myoglobin staining was observed in only 10.3% of 107 cases, a "slightly positive" result in 13.1% and a "negative" result in 76.6%. The findings suggest that rhabdomyolysis is a frequent consequence of illicit drug consumption and that it is not promoted by a single factor, but by a combination of several factors.     

Chemical fingerprinting of gasoline. Part 3. Comparison of unevaporated automotive gasoline samples from Australia and New Zealand

A gas chromatography-mass spectrometry with selected ion monitoring (GC-MS (SIM)) method was used to discriminate samples of unevaporated gasoline collected from Auckland, New Zealand and Sydney, Australia. This method was applied to 28 samples of unevaporated gasoline, covering three different grades (regular unleaded, premium unleaded and premium plus unleaded), that were collected from service stations in Auckland, New Zealand in summer (February) and winter (August). The 14 samples of summer gasoline collected in New Zealand could be divided into seven unique groups. The 14 samples of winter gasoline from New Zealand could be divided into 14 unique groups. The 14 samples collected in New Zealand during February 2002 were then compared to 24 samples of unevaporated gasoline collected from service stations in Sydney, Australia during the same month. Most of the samples could be differentiated based on their country of origin.     

Persisting fetal microchimerism does not interfere with forensic Y-chromosome typing

Forensic Y-chromosome typing applies Y-chromosomal polymorphisms to the analysis of male/female mixed stains such as vaginal swabs in rape cases. The sensitivity of this approach exceeds that of cytological techniques combined with autosomal DNA typing. Y-chromosome typing is based on the assumption that Y-chromosomal DNA found in tissue or secretions of women must originate from a male individual, usually the perpetrator. Nevertheless, it was shown recently that fetal cells can migrate into the female body during pregnancy and can persist for decades ("persisting fetal microchimerism"). The body of a woman after a pregnancy with a male embryo can thus display a small fraction of fetal cells with Y-chromosomes. Using high sensitivity PCR protocols (reamplification with nested primers and up to 60 PCR cycles) fetal cells were previously identified in a number of maternal tissues including skin, blood, muscle and solid organs. It is, however, not clear at present, whether these cells can occur in vaginal secretions, and whether they are capable of producing false positive results in forensic Y-chromosome typing. To evaluate these questions, 66 blood samples of women with at least one son and nine vaginal swabs of women without sexual intercourse in the last 2 weeks were amplified for a stretch of the SRY gene. Eight thyroid gland tissues with already established male fetal microchimerism were used as positive control samples. Blood samples of 10 young girls without history of pregnancy were used as negative controls. Using a PCR with 10 ng of extracted DNA and 30 PCR cycles ("routine sensitivity assay") none of the samples yielded positive results. However, in a PCR with 200 ng of extracted DNA and 45 PCR cycles ("high sensibility assay"), 14% of the blood samples of mothers and 33% of the vaginal swabs amplified for SRY. Our results thus show that increasing the sensitivity of the PCR method and the amount of template DNA produce positive results while protocols used for routine Y-chromosomal typing with small amounts of DNA (approximately 10 ng of DNA) and with a limited number of PCR cycles (approximately 30) can clearly eliminate this peril.