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.     

Intimate partner violence during pregnancy and mothers' child abuse potential

This research examines whether women who have experienced intimate partner violence (IPV) during pregnancy have a higher child abuse potential than women who have not experienced IPV. Data were analyzed from a longitudinal investigation of IPV during pregnancy. This study recruited 88 pregnant women during prenatal care and followed them for 1(1/2) years. IPV was assessed using the Conflict Tactics Scale 2 (CTS2). The woman's potential for child abuse was assessed using the Child Abuse Potential Inventory (CAPI). There was a significant positive association between IPV and child abuse potential scores (p = .003), even after controlling for sociodemographics. The odds of having a high level of child abuse potential were 3 times greater for women who were victims of IPV compared to nonvictims. Higher child abuse potential scores of the victimized women resulted mainly from the Distress and Problems with Others CAPI scales.     

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.