Abstract Introduction: Different developmental and environmental vulnerability conditions can influence violent behavior in young people. Objectives: To describe the characteristics of young males who were convicted of murder or attempted murder in the province of Buenos Aires, based on indicators of maturity, impulsivity, and socio-family vulnerability. Materials and Methods: Descriptive and exploratory study. The sample consisted of 195 young men (mean: 16.8 years) imprisoned in reformatory institutions of the Province of Buenos Aires, Argentina, as they were convicted of murder (n=130), repeated murder (n=15), or attempted murder (n=50). Self and hetero-informed instruments, and professional assessment scales were used, namely: the Consideration of Future Consequences Scale (CFC); the Psychosocial Maturity Inventory (PSM); the Weinberg Adjustment Inventory (WAI); the Resistance to Peer Influence Questionnaire (RPIQ); the Psychopathy Checklist: Youth Version (PCL:YV); the Inventory of Callous Unemotional Traits (ICU), and the Barrat Impulsiveness Scale version 11 (BIS-11). Results: The distribution of the total BIS 11 and the PSM Individual Adaptation were normal (mean: 62.33 and 6.38, respectively). The mean of the total PCL:YV was 25.87. In 32.8% of the cases a first degree relative was also imprisoned. "Impulsive" and "Non-impulsive" clusters were empirically established. Conclusions: The participants' profile is characterized by several psychological and socio-family vulnerabilities that should be targeted in preventive interventions aimed at preventing violent recidivism.

Resumen Introducción. Diversas condiciones de vulnerabilidad dependientes del desarrollo y de las influencias medioambientales pueden influir en las conductas violentas juveniles. Objetivos. Describir las características de jóvenes que cometieron homicidio o intento de homicidio atendiendo a indicadores de madurez, impulsividad y vulnerabilidad sociofamiliar. Materiales y métodos. Estudio de diseño descriptivo y exploratorio. Los participantes fueron 195 varones jóvenes (media: 16.8 años) institucionalizados en la provincia de Buenos Aires, Argentina, por orden judicial por haber cometido homicidio (n=130), homicidio reiterado (n=15) o tentativa de homicidio (n=50). Se utilizaron instrumentos auto y heteroinformados y las escalas de evaluación profesional Consideration of Future Consequences Scale (CFC), Psychosocial Maturity Inventory (PSM), Weinberg Adjustment Inventory (WAI), Resistance to Peer Influence (RPI), Psychopathy Checklist: Youth Version (PCL:YV), Inventory of Callous Unemotional Traits (ICU) y Barrat Impulsiveness Scale version 11 (BIS 11). Resultados. La distribución de BIS 11 total y de PSM Adecuación Individual fueron normales, con medias de 62.33 y 6.38, respectivamente; la media de PCL: YV total fue 25.87. El 32.8% de los jóvenes tenía familiares de primer grado presos. Se configuraron empíricamente los clusters "impulsivo" y "no impulsivo". Conclusiones. El perfil de los participantes se caracteriza por diversas vulnerabilidades psicológicas y sociofamiliares que deberían ser blanco de intervención preventiva de recidiva violenta.

Abstract The aim of this work was to describe the phenotypic and genotypic variability related to iris color for the population of Buenos Aires province (Argentina), and to assess the usefulness of current methods of analysis for this country. We studied five Single Nucleotide Polymorphisms (SNPs) included in the IrisPlex kit, in 118 individuals, and we quantified eye color with Digital Iris Analysis Tool. The markers fit Hardy-Weinberg equilibrium for the whole sample, but not for rs12913832 within the group of brown eyes (LR=8.429; p=0.004). We found a remarkable association of HERC2 rs12913832 GG with blue color (p < 0.01) but the other markers did not show any association with iris color. The results for the Buenos Aires population differ from those of other populations of the world for these polymorphisms (p < 0,01). The differences we found might respond to the admixed ethnic composition of Argentina; therefore, methods of analysis used in European populations should be carefully applied when studying the population of Argentina. These findings reaffirm the importance of this investigation in the Argentinian population for people identification based on iris color.

Several single nucleotide polymorphisms (SNPs) in the Mu Opioid Receptor gene (OPRM1) have been identified and associated with a wide variety of clinical phenotypes related both to pain sensitivity and analgesic requirements. The A118G and other potentially functional OPRM1 SNPs show significant differences in their allele distributions among populations. However, they have not been properly addressed in a population genetic analysis. Population stratification could lead to erroneous conclusions when they are not taken into account in association studies. The aim of our study was to analyze OPRM1 SNP variability by comparing population samples of the International Hap Map database and to analyze a new population sample from the city of Corrientes, Argentina. The results confirm that OPRM1 SNP variability differs among human populations and displays a clear ancestry genetic structure, with three population clusters: Africa, Asia, and Europe-America.