Probability of exclusion in paternity testing: time to reassess

The average exclusion probability is a measure of efficiency in paternity testing; it refers to the a priori ability of a battery of tests to detect paternity inconsistencies. This parameter measures the capacity of the system to detect a false accusation of paternity. Traditionally, this average exclusion probability has been estimated as the probability of excluding a man who is not the father by an inconsistency in at least one of the studied loci. We suggest that this criterion should be corrected, as currently the presumed father is excluded when at least three genetic inconsistencies are found with the child being tested, not just one. This change of criterion has occurred because of the use of microsatellite loci, whose mutation rates are much greater than those of the coding genes used previously in paternity studies. We propose the use of the average probability of exclusion for at least three loci (not only one), as an honest measure of the combined probability of exclusion of several loci, and we propose an algebraic expression to calculate it.     

Importance of radiological diagnosis applied to necroscopy

The authors evaluate the consequences of incomplete necroscopic examinations wherein it was impossible to apply radiological resources to locate firearm projectiles. The study includes 8185 reports from the Instituto Médico-Legal Afranio Peixoto in Rio de Janeiro, Brazil, representing the totality of corpses processed from January to December 2001; of these, 3122 were gunshot victims, 309 of which were buried with unremoved projectiles, being liable to future judicial reappraisal. During the same period, there were 23 exhumation requests by police authorities, 12 of them querying the existence of projectiles. The authors looked into the formal reasons assumed by the medico legal experts to conclude their reports from incomplete examinations, and suggest that gunshot necroscopic examinations should follow specific protocols, as incomplete autopsies will require further exhumations, at unnecessary additional costs.     

Analysis of STR loci in Cartagena, a Caribbean city of Colombia

Allele frequencies, together with some parameters of forensic interest were estimated for nine STRs included in the AmpF/STR Profiler kit (CSF1PO, D3S1358, D5S818, D7S820, D13S317, FGA, TH01, TPOX and vWA) in a sample of 215 unrelated individuals from Cartagena (Colombia). For all loci, no significant deviations from Hardy-Weinberg equilibrium were observed. Comparative analysis results between our data and those from other Colombian and African population samples revealed significant differences, except with two Colombian Caribbean Coast sub-regions.     

Solid-phase microextraction for the determination of cocaine and cocaethylene in human hair by gas chromatography-mass spectrometry

A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene.     

Genetic variation of 15 STR autosomal loci in the Maracaibo population from Venezuela

Allele frequencies for 15 short tandem repeats (STRs) autosomal loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA, included in the AmpFLSTR Identifiler, Applied Biosystems) were studied in the city of Maracaibo, Venezuela and were compared with other published Latin-American populations for the same loci. Population and forensic parameters were estimated.     

Population genetic data for 18 STR loci in Costa Rica

Allele frequencies for 18 STR autosomal loci (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, D16S539, TH01, TPOX, CSF1PO, Penta D, Penta E, D19S433, D2S1338 and SE33) were obtained from a sample of 191-500 unrelated individuals from Costa Rica, Central America.     

Clientelism or Something Else? Squatter Politics in Montevideo

Through the in‐depth ethnographic study of one squatter neighborhood in Montevideo and its leader's political networks, this article illustrates a successful strategy through which some squatter neighborhoods have fought for their right to the city. This consists of opportunistic, face‐to‐face relationships between squatter leaders and politicians of various factions and parties as intermediaries to get state goods, such as water, building materials, electricity, roads, and ultimately land tenure. Through this mechanism, squatters have seized political opportunities at the national and municipal levels. These opportunities were particularly high between 1989 and 2004, years of great competition for the votes of the urban poor on the periphery of the city, when the national and municipal governments belonged to opposing parties. In terms of theory, the article discusses current literature on clientelism, posing problems that make it difficult to characterize the political networks observed among squatters.