The forensic and investigative significance of reverse paternity testing with absent maternal sample

The authors are involved in the extraction of DNA material from calcified tissues, oftentimes teeth, and analysis of such material to assist the investigative process, frequently by confirming the identity of the victim. Biologic or molecular techniques for the purposes of human identification have evolved to allow increasingly discriminating tests for use in criminal and noncriminal death investigations, as well as paternity disputes. The goal of such tests is to either include 2 samples (ie, they are from the same person, or in the case of paternity, they are from related individuals) or exclude 2 samples (ie, they are from different people or from unrelated individuals). Regardless of the system used and when data error has been eliminated, an exclusionary conclusion is irrefutable. The probability of excluding the falsely accused has steadily increased over the years as new methods are developed. Conventional ABO blood typing, for example, has a probability of exclusion (PE) of only 17%. This value increases to 53% with the inclusion of the Rh and MN systems. Additional serological markers can provide a probability of exclusion of greater than 99%. Today, the current method of choice for human identification is the polymerase chain reaction for the amplification of short tandem repeat (STR) multiplexes. This paper discusses the implications of nonpaternity in reverse paternity testing when only paternal DNA is available.     

Mitochondrial DNA error prophylaxis: assessing the causes of errors in the GEP'02-03 proficiency testing trial

A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.     

Reliability of the methods applied to assess age minority in living subjects around 18 years old. A survey on a Moroccan origin population

We present a review of a population of 114 immigrant Moroccan males for which an age estimation was requested. The subjects' real chronological age was confirmed by the Moroccan Embassy in Spain. The confirmed age range was between 13 and 25, with an average age of 18.1 years and a standard deviation of 2.03. The following tests were performed to arrive at the forensic estimation of age: general physical examination, carpus X-ray (Greulich and Pyle method) and dental orthopantomography to determine the degree of maturity of the third inferior molars (Demirjian's method). Carpus X-ray (skeletal age) was the most useful method, followed by Demirjian's method (dental age), as prediction factors of a chronological age of over or under 18. The combination of skeletal and dental age variables represented a significant improvement in the prediction of the chronological age of the subjects in this population, reducing the number of ethically unacceptable test errors to a minimum.     

Validation of a 21-locus autosomal SNP multiplex for forensic identification purposes

A single nucleotide polymorphism (SNP) multiplex has been developed to analyse highly degraded and low copy number (LCN) DNA template, i.e. <100 pg, for scenarios including mass disaster identification. The multiplex consists of 20 autosomal non-coding loci plus Amelogenin for sex determination, amplified in a single tube PCR reaction and visualised on the Applied Biosystems 3100 capillary electrophoresis (CE) system. Allele-specific primers tailed with shared universal tag sequences were designed to speed multiplex design and balance the amplification efficiencies of all loci through the use of a single reverse and two differentially labelled allele denoting forward universal primers. As the multiplex is intended for use with samples too degraded for conventional profiling, a computer program was specifically developed to aid interpretation. Critical factors taken into account by the software include empirically determined extremes of heterozygous imbalance (Hb) and the drop-out threshold (Ht) defined as the maximum peak height of a surviving heterozygous allele, where its partner may have dropped out. The discrimination power of the system is estimated at 1 in 4.5 million, using a White Caucasian population database. Comparisons using artificially degraded samples profiled with both the SNP multiplex and AMPFISTR SGM plus (Applied Biosystems) demonstrated a greater likelihood of obtaining a profile using SNPs for certain sample types. Saliva stains degraded for 147 days generated an 81% complete SNP profile whilst short tandem repeats (STRs) were only 18% complete; similarly blood degraded for 243 days produced full SNP profiles but only 9% with STRs. Reproducibility studies showed concordance between SNP profiles for different sample types, such as blood, saliva, semen and hairs, for the same individual, both within and between different DNA extracts.     

Prison size,overcrowding, prison violence,and recidivism

Contrary to a widespread belief about the undesirability of relatively large prisons, a review of the criminological literature yields no empirical evidence that prison size influences behavior inside or after leaving prison. The English prison statistics show that prison offenses, and more specifically assaults, are less likely in larger prisons. However, it was impossible in these analyses to control for the kinds of inmates in each prison. In a more controlled analysis of correctional effectiveness (defined as the difference between predicted and actual reconviction rates), there was a strong tendency for the more overcrowded prisons to be less effective. Size was only weakly related to effectiveness, and this association was reduced further after controlling for overcrowding. It was concluded that an important priority for governmental agencies should be to reduce overcrowding in prisons.     

Occurrence of barbiturate, benzodiazepine, meprobamate, methaqualone and phenothiazine in car occupants killed in traffic accidents in the south of Sweden

An investigation of the following psychoactive drugs: barbiturate, benzodiazepine, meprobamate, methaqualone and phenothiazine, was performed on all automobile occupants killed in accidents in southern Sweden during 1977 and 1978. Of 122 drivers and 55 passengers analysed, low concentrations of these drugs were found in nine drivers and in five passengers. Thus, 7.3% of the drivers were driving under the influence of drugs and, of these, two drivers (1.6% of all analysed drivers) were also inebriated. Twenty-three per cent of the drivers were inebriated only. According to the circumstances in the accidents and the number of drivers whose analyses proved positive, drug influence seldom seems to be the cause of fatal traffic accidents.