Andréa Carla de Souza Góes

Population and mutation analysis of 17 Y-STR loci from Rio de Janeiro (Brazil)

The 17 Y chromosome STR loci DYS19, DYS385, DYS389I and II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10 were analyzed in a male sample of 126 unrelated individuals from Rio de Janeiro. No shared haplotypes were observed, demonstrating the usefulness and informative power of these Y-STRs in male lineage identification in Rio de Janeiro. Pairwise haplotype analysis showed no significant differences in the comparison of Rio de Janeiro with Iberian samples from different regions of Portugal and Spain, as well as with other Caucasian samples from South America, namely Costa Rica, Buenos Aires (Argentina) and São Paulo (Brazil). The same set of Y-STRs was also typed in 119 father/son pairs and among 2,023 allele transfers, 8 mutations were observed with an overall mutation rate of 0.003955±0.001396 per locus/meiosis across the 17 loci. Except in one case, all mutations were single step. For DYS438 a four-step mutation was found which has never been reported before, where allele 10 mutated to allele 6.

A decade of human genome project conclusion: Scientific diffusion about our genome knowledge

The Human Genome Project (HGP) was initiated in 1990 and completed in 2003. It aimed to sequence the whole human genome. Although it represented an advance in understanding the human genome and its complexity, many questions remained unanswered. Other projects were launched in order to unravel the mysteries of our genome, including the ENCyclopedia of DNA Elements (ENCODE). This review aims to analyze the evolution of scientific knowledge related to both the HGP and ENCODE projects. Data were retrieved from scientific articles published in 1990–2014, a period comprising the development and the 10 years following the HGP completion. The fact that only 20,000 genes are protein and RNA‐coding is one of the most striking HGP results. A new concept about the organization of genome arose. The ENCODE project was initiated in 2003 and targeted to map the functional elements of the human genome. This project revealed that the human genome is pervasively transcribed. Therefore, it was determined that a large part of the non‐protein coding regions are functional. Finally, a more sophisticated view of chromatin structure emerged. The mechanistic functioning of the genome has been redrafted, revealing a much more complex picture. Besides, a gene‐centric conception of the organism has to be reviewed. A number of criticisms have emerged against the ENCODE project approaches, raising the question of whether non‐conserved but biochemically active regions are truly functional. Thus, HGP and ENCODE projects accomplished a great map of the human genome, but the data generated still requires further in depth analysis.

DNA typing from vaginal smear slides in suspected rape cases

In an investigation of suspected rape, proof of sexual assault with penetration is required. In view of this, detailed descriptions of the genitalia, the thighs and pubic region are made within the forensic medical service. In addition, vaginal swabs are taken from the rape victim and some of the biological material collected is then transferred to glass slides. In this report, we describe two rape cases solved using DNA typing from cells recovered from vaginal smear slides. In 1999, two young women informed the Rio de Janeiro Police Department that they had been victims of sexual assaults. A suspect was arrested and the victims identified him as the offender. The suspect maintained that he was innocent. In order to elucidate these crimes, vaginal smear slides were sent to the DNA Diagnostic Laboratory for DNA analysis three months after the crimes, as unique forensic evidence. To get enough epithelial and sperm cells to perform DNA analysis, we used protocols modified from the previously standard protocols used for DNA extraction from biological material fixed on glass slides. The quantity of cells was sufficient to perform human DNA typing using nine short tandem repeat (STR) loci. It was 3.3 billion times more probable that it was the examined suspect who had left sperm cells in the victims, rather than any other individual in the population of Rio de Janeiro.

Molecular alterations and tumor suppressive function of the DUSP22 (Dual Specificity Phosphatase 22) gene in peripheral T-cell lymphoma subtypes

Monoallelic 6p25.3 rearrangements associated with DUSP22 (Dual Specificity Phosphatase 22) gene silencing have been reported in CD30+ peripheral T-cell lymphomas (PTCL), mostly with anaplastic morphology and of cutaneous origin. However, the mechanism of second allele silencing and the putative tumor suppressor function of DUSP22 have not been investigated so far. Here, we show that the presence, in most individuals, of an inactive paralog hampers genetic and epigenetic evaluation of the DUSP22 gene. Identification of DUSP22-specific single-nucleotide polymorphisms haplotypes and fluorescence in situ hybridization and epigenetic characterization of the paralog status led us to develop a comprehensive strategy enabling reliable identification of DUSP22 alterations. We showed that one cutaneous anaplastic large T-cell lymphomas (cALCL) case with monoallelic 6p25.3 rearrangement and DUSP22 silencing harbored exon 1 somatic mutations associated with second allele inactivation. Another cALCL case carried an intron 1 somatic splice site mutation with predicted deleterious exon skipping effect. Other tested PTCL cases with 6p25.3 rearrangement exhibited neither mutation nor deletion nor methylation accounting for silencing of the non-rearranged DUSP22 allele, thus inactivated by a so far unknown mechanism. We also characterized the expression status of four DUSP22 splice variants and found that they are all silenced in cALCL cases with 6p25.3 breakpoints. We finally showed that restoring expression of the physiologically predominant isoform in DUSP22-deficient malignant T cells inhibits cellular expansion by stimulating apoptosis and impairs soft agar clonogenicity and tumorigenicity. This study therefore shows that DUSP22 behaves as a tumor suppressor gene in PTCL.

Eight short tandem repeats (STR) frequencies for descendants from Terena indigenous Brazilian group.

POPULATION descendants from Terenas an indigenous group.

Identification of a criminal by DNA typing in a rape case in Rio de Janeiro, Brazil

CONTEXT Human DNA identification is a powerful tool for paternity cases as well as for criminal investigation, in which biological evidence is typed after collection from crime scenes and for the identification of human remains. OBJECTIVE Identification of a criminal in a rape case with 4 suspects using STR and VNTR DNA analysis. TYPE OF STUDY Forensic DNA analysis. SETTING DNA Diagnostic Laboratory, Universidade Estadual do Rio de Janeiro, Brazil. PARTICIPANTS Blood from 4 suspects and the victim, and skin from the fetus. PROCEDURES Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). RESULTS Three of the suspects were excluded and one of them was identified as the biological father of the fetus after typing with CTT and FFv Multiplexes. Complementary DNA typing at 3 VNTR loci was also carried out. CONCLUSIONS After typing four suspects using 6 STR loci, one of them was identified as the biological father of the fetus. In order to significantly enhance the Combined Paternity Index (PI), complementary DNA typing in 3 VNTR loci was carried out. The included suspect was found to be the biological father with a PI of 412,860 (Probability of Paternity: 99.9997%).

Projeto Genoma Humano: um retrato da construção do conhecimento científico sob a ótica da revista Ciência Hoje

Em abril de 2003, o Projeto Genoma Humano (PGH), que havia sido iniciado em 1989, foi finalizado. Objetivamos, neste trabalho, relatar a evolucao do conhecimento cientifico que culminou na proposicao da sequencia de nucleotideos do genoma humano sob a otica da revista Ciencia Hoje (CH), pioneira na popularizacao de ciencia no Brasil. Analisamos a divulgacao do PGH na revista CH de dezembro de 1984 a dezembro de 2010, intervalo que compreende: a motivacao do sequenciamento do genoma humano, a fundacao das instituicoes responsaveis pelo projeto e prosseguimento do PGH, a rivalidade com a empresa privada Celera Genomics, a publicacao do primeiro rascunho, e consequencias imediatas do projeto. Esperamos que a compreensao do pensamento reinante na epoca e dos estilos envolvidos nesse processo contribua para uma visao mais adequada da producao do conhecimento cientifico relacionado ao PGH e para a melhoria da educacao cientifica de professores de biologia e de ciencias.

A obra Admirável mundo novo no ensino interdisciplinar: fonte de reflexões sobre Ciência, Tecnologia e Sociedade

EnglishThis study explored the impact of using science fiction associated to socioscientific issues in the moral and reasoning development of students and the consequent awakening to citizenship. We developed and applied a didactic sequence, in a Freirean perspective, based on Brave new world novel, for high school students. The didactic sequence is grounded in the discussion and debates about support material prepared for the following socioscientific issues, highlighted from the novel: consumerism, drug use, genetic manipulation and social exclusion. The didactic intervention was evaluated through a questionnaire. We verified the students developed a critical sense by relating contemporary socioscientific issues to the society created by Aldous Huxley in 1932. The students perceived the activity as interdisciplinary, relating the addressed topics to various disciplines and evaluated the alternative pedagogical practice as positive. The students also recognized these issues are related not only to their life in society but to existential human condition. portuguesDiscutimos o impacto da utilizacao da ficcao cientifica, associada ao enfoque Ciencia, Tecnologia e Sociedade (CTS), no desenvolvimento critico dos alunos e o consequente despertar para o exercicio da cidadania. Para tal, aplicamos uma sequencia didatica para alunos do ensino Medio, baseada na obra Admiravel mundo novo, em uma perspectiva Freireana. A atividade e fundamentada na discussao, a partir de material de apoio preparado para os temas CTS destacados da obra: consumismo, uso de drogas, manipulacao genetica e exclusao social. A intervencao foi avaliada por meio de questionario. Verificamos o desenvolvimento do senso critico dos alunos atraves das relacoes das tematicas CTS da sociedade contemporânea com a sociedade criada por Aldous Huxley em 1932. Os alunos perceberam a atividade como interdisciplinar, relacionando os temas abordados com varias disciplinas, e valorizaram a pratica pedagogica alternativa. Os estudantes tambem reconheceram que as tematicas expostas e debatidas relacionam-se nao so a vida em sociedade como a condicao existencial humana.