Este trabajo demuestra que los genes que codifican para los enzimas beta-galactosido alfa-2,3-sialiltransferasa 3 (ST3Gal III), y en menor medida beta-galactosido alfa-2,3-sialiltransferasa 4 (ST3Gal IV), están directamente implicados en etapas clave de la progresión tumoral como la adhesión, la migración y la formación de metástasis en las líneas de adenocarcinoma pancreático humano Capan-1 y MDAPanc-28. También, que las Especies Reactivas del Oxígeno (ROS) generadas durante los procesos de proliferación y diferenciación celular o debido a estímulos oxidantes externos, desempeñan un importante papel en el control de la síntesis de ST3Gal III y SLex, y por lo tanto en la regulación del fenotipo metastático. Además, junto al papel pro-adhesivo de la E-Selectina, este trabajo ha descrito efectos prometastáticos adicionales para esta molécula como inductora de la migración y de la secreción de VEGF a través de un mecanismo E-Selectina-SLex dependiente. / This work shows that genes that codifying for the enzymes beta-galactoside alpha-2,3-sialyltransferase 3 (ST3Gal III), and in a lower extent beta-galactoside alpha-2,3-sialyltransferase 4 (ST3Gal IV) , are directly implicated in key steps of tumour progression such as adhesion, migration and metastasis formation in the pancreatic adenocarcinoma cell lines Capan-1 and MDAPanc-28. Moreover, Reactive Oxygen Species (ROS) generated in these cell lines during cell proliferation-differentiation processes or by external oxidant stimuli, play a role in the control of ST3Gal III and SLex levels and in the acquisition of a more aggressive phenotype. And, together with the pro-adhesive role of E-Selectin for circulating cells, this work uncovers sE-Selectin dependent migration and VEGF secretion through a SLex depending mechanism, supporting additional pro-metastatic effects for sE-Selectin-SLex interaction.

Embargoed till 18 November 2011 / No abstract available.

Central infusion of the hexapeptide angiotensin IV (Ang IV) and its analogs have been demonstrated to markedly enhance memory retention and retrieval in rats using a range of learning and memory paradigms. This effect is mediated by the binding of the peptide to the specific binding site previously described as the AT4 receptor. The AT4 receptor has been isolated and identified as insulin-regulated aminopeptidase (IRAP), a type II transmembrane protein belonging to the M1 family of zinc-dependent aminopeptidases. Subsequently, AT4 receptor ligands, including Ang IV and its analogues and the unrelated peptide LVV-hemorphin-7, were demonstrated to be peptide inhibitors of IRAP. These findings suggest that AT4 ligands may exert their cognitive effects by inhibiting the catalytic activity of IRAP in the brain. Therefore, IRAP is an important target for the development of a new class of therapeutic agents for the treatment of memory loss. / To characterize IRAP at the molecular level and identify non-peptide inhibitors of IRAP for drug development, the aims of this study were to: 1) determine whether IRAP exists as a homodimer; 2) identify cysteine residue(s) involved in IRAP dimerization; 3) investigate the roles of the conserved residues of the HEXXH(X)18E Zn2+-binding motif and the GAMEN motif in substrate/inhibitor binding using site-directed mutagenesis; 4) use a molecular model of the catalytic domain of IRAP based on the crystal structure of a related M1 family metallopeptidase to: (i) identify key residues required for substrate/inhibitor binding; (ii) identify and characterize non-peptide IRAP inhibitors from a compound database by in silico virtual screening based on the homology model of IRAP. / Co-immunoprecipitation followed by Western blotting of IRAP under reducing and non-reducing conditions showed IRAP exists both as covalently- and non-covalently-bound homodimers. Serine scanning of cysteine residues potentially involved in forming inter-molecule disulfide-bonds was performed. Mutational analyses indicated that covalent homodimerization of IRAP is due to more than one cysteine residue. Limited trypsin digestion followed by co-immunoprecipitation suggests that non-covalent homodimerization of IRAP involves residues/regions within the last 130 amino acids of the protein. / The catalytic site of IRAP contains two consensus motifs, the H464EXXH468(X)18E487 Zn2+-binding motif and the G428AMEN432 motif. The role of conserved residues with these motifs was investigated using site-directed mutagenesis and pharmacological analyses. The conserved His and Glu residues of the Zn2+-binding motif were shown to be essential for IRAP catalytic activity. This was also observed for the Met and Glu residues of the GAMEN motif, while Asn mutant retained some catalytic activity. Residues important for substrate or inhibitor binding were identified as Gly, Ala and Asn. / A molecular model of the catalytic domain of IRAP based on the crystal structure of a homologous M1 metallopeptidase, leukotriene A4 hydrolase (LTA4H) was used to compare the catalytic sites of IRAP and LTA4H, and identified two amino acids at the putative substrate-binding pocket: Ala427 and Leu483 in IRAP, and the corresponding residues Tyr267 and Phe314 in LTA4H. A mutational analysis involving substitution of Ala427 and Leu483 with the corresponding residues revealed Ala427 and Leu483 characterize the enzyme S1 subsite, influencing the affinity and placement of substrates and peptide inhibitors in the catalytic site. / The molecular model of IRAP was also used for virtual screening of compound databases to identify novel non-peptide inhibitors. After two rounds of in silico screening, a family of compounds was identified and shown to be specific and competitive inhibitors of IRAP. Preliminary results suggest that one of these inhibitors, referred to as HFI 142, may possess memory-enhancing properties. The identification of non-peptide IRAP inhibitors will assist in pharmacological studies aimed at understanding the molecular mechanisms of IRAP aminopeptidase activity and physiological role of IRAP. In addition, the new inhibitors have the potential to form the basis for the development of a novel class of drugs useful for treating memory disorders.

Embargoed till 18 November 2011 / No abstract available.

No description available.

Issus d’une dynastie de maîtres maçons et d’architectes établis à Dreux vers 1500-1516, les frères Louis et Clément Métézeau sont des architectes français actifs de la fin du XVIe siècle à la première moitié du XVIIe. La carrière du premier, Louis (vers 1563 ?-1615), essentiellement parisienne, se confond avec le règne d’Henri IV et se prolonge jusqu’en 1615 sous la régence de Marie de Médicis. En 1594, il fut chargé de superviser tous les chantiers royaux et fut, à ce titre, un des principaux acteurs de la reconstruction et de la modernisation du royaume. Son frère cadet, Clément (1581-1652), suivit ses traces : un temps au service des ducs de Lorraine et de Nevers, il revint en France où il devint à partir de 1615 un des architectes et ingénieurs ordinaires du roi Louis XIII puis de son frère Gaston d’Orléans. Il répondit aussi à de nombreuses commandes privées, tant civiles que religieuses, mais c’est la digue de La Rochelle qui fit sa renommée.A partir de documents d’archives inédits et d’une iconographie plus riche qu’on pourrait imaginer a priori, cette thèse restitue et réévalue les carrières méconnues de ces deux architectes. Une lecture critique des sources inédites rétablit la chronologie de chacune de leurs œuvres et s’attache à répondre aux problèmes récurrents d’attribution. Elle met aussi l’accent sur la polyvalence de ces artistes qu’elle replace au sein même de la communauté artistique parisienne de l’époque. Elle tente enfin de définir, pour chacun, un style architectural mis en regard avec la production des « ancêtres » de la dynastie, puis avec celle de leurs confrères. / Born into a dynasty of builders and architects settled in Dreux around 1500-1516, the brothers Louis and Clément Métézeau are French architects of the end of the sixteenth century and the first half of the seventeenth century. The career of the elder, Louis (ca. 1563?-1615), essentially concentrated around Paris, parallels with the reign of Henri IV and continues until 1615 under the regency of Marie de Médicis. In 1594, he was chosen to supervise all the royal building sites. He was one of the major actors of the reconstruction and the modernisation of the kingdom. His younger brother, Clément (1581-1652), followed his example. After working for the dukes of Lorraine and Nevers, he came back to France where he became in 1615 one of the ordinary architects and engineers of the king Louis XIII and his brother Gaston d’Orléans. He carried on several private projects, both civil and religious, but he became famous with his dike of La Rochelle.Using unpublished archive documents, this dissertation revives the unknown careers of both of these architects. A critical reading of the sources provides us with a new chronology of their works and tries to answer the numerous questions concerning their works, especially the recurrent issues of the attribution of their buildings.

Introdução: Mucopolissacaridose IVA ou Síndrome de Morquio A é uma doença autossômica recessiva causada pela deficiência da enzima lisossomal Nacetilgalactosamina- 6-sulfatase (GALNS), que resulta no acúmulo lisossomal dos glicosaminoglicanos: Queratan sulfato e Condroitin-6-sulfato nos tecidos causando as manifestações clínicas. Os fenótipos variam da forma clássica à forma atenuada, ambas sem comprometimento cognitivo. A prevalência de MPS IVA varia de 1/76.000 a 1/640.000 nascidos vivos. Objetivos: Analisar e caracterizar o genótipo de pacientes brasileiros com MPS IVA através de estudos de mutações no gene da GALNS, possibilitando a estimativa de frequência de mutações recorrentes e o estabelecimento um protocolo de rotina para triagem dessas mutações. Métodos: Análise molecular do gene da GALNS foi realizada em 26 pacientes brasileiros inicialmente através de PCR-ARMS para detecção de seis mutações recorrentes (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C e p.S341R) seguidas pela amplificação de regiões codificantes por PCR e sequenciamento. Resultados: Essas mutações foram encontradas em 61,5% da nossa amostra, com uma frequência alélica de 55,8%. Destas, a mutação mais frequente foi p.S341R (26,9%), seguida de p.R386C (21,1%) e p.G116S (7,7%). As mutações p.N164T, p.G139S, p.L307P não foram encontradas em nossa amostra. Além destas, foi encontrada por sequenciamento do éxon 5 uma mutação nova p.C165Y. Conclusão: O protocolo usado para detecção de mutações comuns mostrou-se adequado como um screening inicial de mutações no gene da GALNS, identificando mutações em 61,5% dos pacientes e permitiu a caracterização de 55,8% dos alelos. A mutação p.S341R foi encontrada apenas em pacientes do Nordeste. A identificação de indivíduos heterozigotos nessas famílias será importante para aconselhamento genético e para estimar a prevalência da doença nessa região. Estudos adicionais para identificação da origem dessa mutação, incluindo análises de segregação e haplótipo estão em andamento, e serão avaliadas em conjunto com dados epidemiológicos. / Background: Mucopolysaccharidosis IVA or Morquio A syndrome, is an autosomal recessive disorder caused by deficiency of lysosomal enzyme Nacetylgalactosamine- 6-sulfatase (GALNS), which results in lysosomal storage of glycosaminoglycans: Keratan sulfate and Chondroitin-6-sulfate in tissues causing clinical manifestations. The phenotypes vary from the classical to attenuated form, both without cognitive impairment. The prevalence of MPS IVA ranges from 1/76.000 to 1/640.000 live births. Objective: To analyze and characterize the genotype of Brazilian patients with MPS IVA, through molecular study of mutations in the GALNS gene, enabling the estimative of frequency of recurrent mutations and the establishment of a protocol for routine screening of these mutations. Methods: Molecular analysis of GALNS gene was performed in 26 Brazilian patients initially by ARMS-PCR to detect six recurrent mutations (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C and p.S341R) followed by amplification of coding regions by PCR and sequencing. Results: These mutations were found in 61.5% of our sample, which were present in 55.8% of the alleles. The most frequent mutation was p.RS341R (26.9%), followed by p.R386C (21.1%) and p.G116S (7.7%). Mutations p.N164T, p.G139S, p.L307P were not found in our sample. A novel mutation p.C165Y was found after sequencing of exon 5. Conclusion: The protocol used for detection of common mutations was shown to be adequate for a first screening of mutations at the GALNS gene, once it identified the genotype in 61.5% of patients and allowed the characterization of 55.8% of alleles. The p.S341R was found only in patients from the Northeast. The identification of heterozygous individuals within these families will be important for genetic counseling and for estimating the disease prevalence in this region. Further studies to identify the origin of this mutation, including haplotype and segregation analyses are in progress, and will be evaluated in conjunction with epidemiological data.

Submitted by Alessandra Portugal (alessandradf@ioc.fiocruz.br) on 2013-09-20T16:04:23Z No. of bitstreams: 1 RAFAEL CARVALHO TORRES.pdf: 4075176 bytes, checksum: 19fc00e0161a371b5fb7c118bba5a10a (MD5) / Made available in DSpace on 2013-09-20T16:04:23Z (GMT). No. of bitstreams: 1 RAFAEL CARVALHO TORRES.pdf: 4075176 bytes, checksum: 19fc00e0161a371b5fb7c118bba5a10a (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / Os roedores neotropicais do gênero Oligoryzomys possuem ampla distribuição geográfica, distribuindo-se por toda América Latina. No Brasil, existem pelo menos 12 espécies, com representantes em todos os domínios morfoclimáticos. Entre essas espécies, Oligoryzomys nigripes possui a distribuição mais ampla, ocorrendo por toda a Mata Atlântica, do Rio Grande do Norte ao Rio Grande do Sul (incluindo regiões adjacentes do Paraguai e Argentina), nos Pampas gaúchos e uruguaios e regiões de Cerrado em São Paulo e Goiás. Membros do gênero Oligoryzomys desempenham papel fundamental na dispersão e transmissão de hantaviroses, e estudos populacionais e filogenéticos de espécies de mamíferos reservatórios ajudam a entender a distribuição e a dinâmica dos ciclos de transmissão da doença. Com esse trabalho, pretendemos estudar a diversidade genética de Oligoryzomys, através de filogenias moleculares com marcadores mitocondriais (genes citocromo b e citocromo oxidase subunidade I) e um marcador nuclear (íntron 7 do gene beta-fibrinogênio); analisar a diversidade intraespecífica de O. nigripes, através de análises populacionais e filogeográficas de subpopulações de Goiás, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul e Paraguai, com os dois marcadores mitocondriais citados acima; revisar o status taxônomico de O. utiaritensis, considerado atualmente sinônimo júnior de O. nigripes, através de análises filogenéticas e morfométricas; e investigar se existem inserções nucleares de genes mitocondriais em espécies de Oligoryzomys, um estudo importante levando-se em consideração que a maior parte dos estudos evolutivos desse grupo incluem o sequenciamento de genes mitocondriais. Os resultados mostram que Oligoryzomys é um gênero monofilético, contendo pelo menos quatro grupos de espécies. A diversidade de Oligoryzomys é subestimada, e existem pelo menos quatro espécies não descritas, além da presença de espécies crípticas. Oligoryzomys diferenciou-se dos outros orizomíneos no final do Mioceno e início do Plioceno, há aproximadamente 6,5 milhões de anos, sendo a espécie O. microtis a espécie mais antiga (2,5 milhões de anos) e O. destructor a espécie mais recente (23 mil anos). As análises populacionais indicam uma estruturação genética incipiente entre subpopulações de O. nigripes do Sudeste e Sul do Brasil, mas a diferenciação entre as subpopulações dentro dessas regiões é pequena. A área de diferenciação original de O. nigripes é a região do sul do Brasil, e pelo menos duas frentes de colonização ocorreram: uma em direção ao Paraguai e outra em direção ao centro e sudeste do Brasil. Oligoryzomys utiaritensis é uma espécie válida, distinta de O. nigripes através da morfologia, morfometria, filogenia molecular e citogenética. Existem inserções de sequências mitocondriais no genoma nuclear de pelo menos cinco espécies de Oligoryzomys. Estudos evolutivos devem vir acompanhados de outros tipos de marcadores moleculares, além de informações morfológicas, geográficas e citogenéticas, para um melhor entendimento das relações complexas entre as espécies de Oligoryzomys. / The neotropical rodents of genera Oligoryzomys have a wide distribution, extending throughout Latin America. In Brazil, there are at least 12 species, with representatives in all morphoclimatic domains. Among these species, Oligoryzomys nigripes has the widest distribution, occurring throughout Atlantic Forest of Rio Grande do Norte to Rio Grande do Sul (including adjacent areas of Paraguay and Argentina), Pampas from Brazil and Uruguay, and Cerrado regions of São Paulo e Goiás. Some Oligoryzomys species play a fundamental role in the dispersion and transmission of hantaviruses, and population and phylogenetics studies of mammal reservoirs help to understand the distribution and dynamics of disease transmission cycles. In this work, we intend to study the genetic diversity of Oligoryzomys through molecular phylogeny with mitochondrial markers (cytochrome b and cytochrome oxidase subunit I genes) and a nuclear marker (intron 7 of beta-fibrinogen gene); analyze the intraspecific diversity of O. nigripes via population and phylogeographic studies of subpopulations of Goiás, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul and Paraguay, with the two mitochondrial markers cited above; review the taxonomic status of O. utiaritensis, currently considered a junior synonym of O. nigripes, by morphometric analyses and molecular phylogenetics; and investigate whether there are insertions of mitochondrial genes in nuclear genome of Oligoryzomys species, a relevant study if we account that the most evolutionary studies of this group relies on sequencing mitochondrial genes. Results showed here indicate that Oligoryzomys is a monophyletic genus, containing at least four groups of species. The diversity of Oligoryzomys is underestimated, and there are at least four undescribed species, and the presence of cryptic species. Oligoryzomys has differentiated from other oryzomyinies in late Miocene and early Pliocene, about 6.5 million years ago, O. microtis is the oldest species (2.5 million years) and O. destructor the most recent (23.000 years). Population analyzes indicate an incipient genetic structure between subpopulations of O. nigripes from southeast and south of Brazil, but differentiation among subpopulations within these regions is small. The original area of original differentiation of O. nigripes is the region of southern Brazil, and there were at least two fronts of colonization: one to Paraguay and another toward center and southeast of Brazil. Oligoryzomys utiaritensis is a valid species, distinct from O. nigripes by morphology, morhometrics, cytogenetics and molecular phylogeny. There are insertions of mitochondrial origin into nuclear genome of at least five species of Oligoryzomys. Evolutionary studies should be followed by other types of molecular markers, and morphological, geographical and cytogenetics data, to a better understanding of the complex relationships among Oligoryzomys species.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In recent years there has been an increase in researches for new enzyme inhibitors on medicinal plants used in the treatment of disorders such as schizophrenia, anxiety, amnesia, different stages of depression and bipolar affective disorder. The study of enzymatic inhibitors of prolyl oligopepetidase (POP) and acetylcholinesterase (AChE) are directly related to the treatment of central nervous sistem diseases. In a research with the species Hypericum brasiliense, native from Brazil, it was isolated as main secondary metabolite the chlorogenic acid, a compound able to inhibit POP and AChE. From this observation, three series of chlorogenic, caffeic and cinnamic acids derivatives were obtained through simple derivatization reactions and coupling with the amino acid proline. The derivatives were obtained by usual acetylation, methylation and esterification reactions with satisfactory yields of 50-90%. The couplings with the proline methyl ester were performed using either O-(7- azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU)/ diisopropylethylamine (DIEA) in dimethylformamide or isobutyl chloroformate/ Nmethylmorpholine in tetrahydrofuran. The derivatives were tested against the enzymes POP, AChE and dipeptidyl oligopeptidase (DPP IV). Also, a study was conducted to determine the antibacterial and antifungal activities of all derivatives. The capacity of the tested compounds to inhibit DPP IV and AChE was not exceptional. In contrast, the derivatives methyl ester and 1,7-acetonide obtained from chlorogenic acid, and caffeic acid and its methyl ester derivative showed selectivity and satisfactory performance as POP inhibitors, with IC50 values of 3 to 14 μM. All compounds showed moderate antimicrobial activity. / Nos últimos anos observa-se uma intensificação nas pesquisas por novos inibidores enzimáticos produzidos por plantas medicinais usadas no tratamento de transtornos mentais, tais como esquizofrenia, ansiedade, amnésia, diferentes estágios de depressão e o transtorno afetivo bipolar. O estudo de inibidores das enzimas prolil oligopepetidase (POP) e acetilcolinesterase (AChE), estão diretamente relacionados ao tratamento de tais enfermidades do sistema nervoso central (SNC). Em um trabalho com a planta medicinal Hypericum brasiliense, nativa do Brasil, foi isolado como um dos principais metabólitos secundários o ácido clorogênico, que demonstrou ter capacidade de inibir a POP e a AChE. A partir desta observação, foram obtidas três séries de derivados do ácido clorogênico, do ácido cafeico e do ácido cinâmico através de técnicas simples de derivatização e acoplamento com a prolina metil éster. Os derivados foram obtidos através de técnicas usuais de acetilação, metilação e esterificação, com rendimentos satisfatórios de 50-90 %. Já os acoplamentos com a prolina metil éster foram realizados com hexafluorofosfato de O-(7-azabenzotriazol-1-il)-N,N,N',N'- tetrametiluronio (HATU)/ diisopropiletilamina (DIEA) em dimetilformamida ou cloroformato de isobutila/ N-metilmorfolina em tetraidrofurano. Estes compostos foram avaliados quanto à capacidade inibitória das enzimas POP e AChE, bem como foram testados frente a enzima dipeptidil peptidade IV (DPP IV). Também foi realizado um estudo da atividade antimicrobiana dos derivados obtidos. Os resultados obtidos indicaram que, frente à DPP IV e AChE, os compostos avaliados não demonstraram significativa capacidade inibitória. Entretanto, o derivado metil éster e 1,7-acetonídeo obtidos a partir do ácido clorogênico, o cafeoato de metila e o próprio ácido cafeico mostraram capacidade inibitória seletiva para a POP, com valores de IC50 entre 3 e 14 μM. Com relação à atividade antimicrobiana, os derivados apresentaram moderada ação bactericida, destacando-se os compostos derivados do ácido cinâmico por serem fungicidas.

Introdução: Mucopolissacaridose IVA ou Síndrome de Morquio A é uma doença autossômica recessiva causada pela deficiência da enzima lisossomal Nacetilgalactosamina- 6-sulfatase (GALNS), que resulta no acúmulo lisossomal dos glicosaminoglicanos: Queratan sulfato e Condroitin-6-sulfato nos tecidos causando as manifestações clínicas. Os fenótipos variam da forma clássica à forma atenuada, ambas sem comprometimento cognitivo. A prevalência de MPS IVA varia de 1/76.000 a 1/640.000 nascidos vivos. Objetivos: Analisar e caracterizar o genótipo de pacientes brasileiros com MPS IVA através de estudos de mutações no gene da GALNS, possibilitando a estimativa de frequência de mutações recorrentes e o estabelecimento um protocolo de rotina para triagem dessas mutações. Métodos: Análise molecular do gene da GALNS foi realizada em 26 pacientes brasileiros inicialmente através de PCR-ARMS para detecção de seis mutações recorrentes (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C e p.S341R) seguidas pela amplificação de regiões codificantes por PCR e sequenciamento. Resultados: Essas mutações foram encontradas em 61,5% da nossa amostra, com uma frequência alélica de 55,8%. Destas, a mutação mais frequente foi p.S341R (26,9%), seguida de p.R386C (21,1%) e p.G116S (7,7%). As mutações p.N164T, p.G139S, p.L307P não foram encontradas em nossa amostra. Além destas, foi encontrada por sequenciamento do éxon 5 uma mutação nova p.C165Y. Conclusão: O protocolo usado para detecção de mutações comuns mostrou-se adequado como um screening inicial de mutações no gene da GALNS, identificando mutações em 61,5% dos pacientes e permitiu a caracterização de 55,8% dos alelos. A mutação p.S341R foi encontrada apenas em pacientes do Nordeste. A identificação de indivíduos heterozigotos nessas famílias será importante para aconselhamento genético e para estimar a prevalência da doença nessa região. Estudos adicionais para identificação da origem dessa mutação, incluindo análises de segregação e haplótipo estão em andamento, e serão avaliadas em conjunto com dados epidemiológicos. / Background: Mucopolysaccharidosis IVA or Morquio A syndrome, is an autosomal recessive disorder caused by deficiency of lysosomal enzyme Nacetylgalactosamine- 6-sulfatase (GALNS), which results in lysosomal storage of glycosaminoglycans: Keratan sulfate and Chondroitin-6-sulfate in tissues causing clinical manifestations. The phenotypes vary from the classical to attenuated form, both without cognitive impairment. The prevalence of MPS IVA ranges from 1/76.000 to 1/640.000 live births. Objective: To analyze and characterize the genotype of Brazilian patients with MPS IVA, through molecular study of mutations in the GALNS gene, enabling the estimative of frequency of recurrent mutations and the establishment of a protocol for routine screening of these mutations. Methods: Molecular analysis of GALNS gene was performed in 26 Brazilian patients initially by ARMS-PCR to detect six recurrent mutations (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C and p.S341R) followed by amplification of coding regions by PCR and sequencing. Results: These mutations were found in 61.5% of our sample, which were present in 55.8% of the alleles. The most frequent mutation was p.RS341R (26.9%), followed by p.R386C (21.1%) and p.G116S (7.7%). Mutations p.N164T, p.G139S, p.L307P were not found in our sample. A novel mutation p.C165Y was found after sequencing of exon 5. Conclusion: The protocol used for detection of common mutations was shown to be adequate for a first screening of mutations at the GALNS gene, once it identified the genotype in 61.5% of patients and allowed the characterization of 55.8% of alleles. The p.S341R was found only in patients from the Northeast. The identification of heterozygous individuals within these families will be important for genetic counseling and for estimating the disease prevalence in this region. Further studies to identify the origin of this mutation, including haplotype and segregation analyses are in progress, and will be evaluated in conjunction with epidemiological data.