GUILHERME LOPES YAMAMOTO
Projetos de Pesquisa
Unidades Organizacionais
Instituto da Criança, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina
29 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 29
- Rare variants in SOS2 and LZTR1 are associated with Noonan syndrome(2015) YAMAMOTO, Guilherme Lopes; AGUENA, Meire; GOS, Monika; HUNG, Christina; PILCH, Jacek; FAHIMINIYA, Somayyeh; ABRAMOWICZ, Anna; CRISTIAN, Ingrid; BUSCARILLI, Michelle; NASLAVSKY, Michel Satya; MALAQUIAS, Alexsandra C.; ZATZ, Mayana; BODAMER, Olaf; MAJEWSKI, Jacek; JORGE, Alexander A. L.; PEREIRA, Alexandre C.; KIM, Chong Ae; PASSOS-BUENO, Maria Rita; BERTOLA, Debora RomeoBackground Noonan syndrome is an autosomal dominant, multisystemic disorder caused by dysregulation of the RAS/mitogen activated protein kinase (MAPK) pathway. Heterozygous, pathogenic variants in 11 known genes account for approximately 80% of cases. The identification of novel genes associated with Noonan syndrome has become increasingly challenging, since they might be responsible for very small fractions of the cases. Methods A cohort of 50 Brazilian probands negative for pathogenic variants in the known genes associated with Noonan syndrome was tested through whole-exome sequencing along with the relatives in the familial cases. Families from the USA and Poland with mutations in the newly identified genes were included subsequently. Results We identified rare, segregating or de novo missense variants in SOS2 and LZTR1 in 4% and 8%, respectively, of the 50 Brazilian probands. SOS2 and LZTR1 variants were also found to segregate in one American and one Polish family. Notably, SOS2 variants were identified in patients with marked ectodermal involvement, similar to patients with SOS1 mutations. Conclusions We identified two novel genes, SOS2 and LZTR1, associated with Noonan syndrome, thereby expanding the molecular spectrum of RASopathies. Mutations in these genes are responsible for approximately 3% of all patients with Noonan syndrome. While SOS2 is a natural candidate, because of its homology with SOS1, the functional role of LZTR1 in the RAS/MAPK pathway is not known, and it could not have been identified without the large pedigrees. Additional functional studies are needed to elucidate the role of LZTR1 in RAS/MAPK signalling and in the pathogenesis of Noonan syndrome.
- Somatic Mosaic Activating Mutations in PIK3CA Cause CLOVES Syndrome(2012) KUREK, Kyle C.; LUKS, Valerie L.; AYTURK, Ugur M.; ALOMARI, Ahmad I.; FISHMAN, Steven J.; SPENCER, Samantha A.; MULLIKEN, John B.; BOWEN, Margot E.; YAMAMOTO, Guilherme L.; KOZAKEWICH, Harry P. W.; WARMAN, Matthew L.Congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies (CLOVES) is a sporadically occurring, nonhereditary disorder characterized by asymmetric somatic hypertrophy and anomalies in multiple organs. We hypothesized that CLOVES syndrome would be caused by a somatic mutation arising during early embryonic development. Therefore, we employed massively parallel sequencing to search for somatic mosaic mutations in fresh, frozen, or fixed archival tissue from six affected individuals. We identified mutations in PIK3CA in all six individuals, and mutant allele frequencies ranged from 3% to 30% in affected tissue from multiple embryonic lineages. Interestingly, these same mutations have been identified in cancer cells, in which they increase phosphoinositide-3-kinase activity. We conclude that CLOVES is caused by postzygotic activating mutations in PIK3CA. The application of similar sequencing strategies will probably identify additional genetic causes for sporadically occurring, nonheritable malformations.
- Mutations in Fibronectin Cause a Subtype of Spondylometaphyseal Dysplasia with ""Corner Fractures''(2017) LEE, Chae Syng; FU, He; BARATANG, Nissan; ROUSSEAU, Justine; KUMRA, Heena; SUTTON, V. Reid; NICETA, Marcello; CIOLFI, Andrea; YAMAMOTO, Guilherme; BERTOLA, Debora; MARCELIS, Carlo L.; LUGTENBERG, Dorien; BARTULI, Andrea; KIM, Choel; HOOVER-FONG, Julie; SOBREIRA, Nara; PAULI, Richard; BACINO, Carlos; KRAKOW, Deborah; PARBOOSINGH, Jillian; YAP, Patrick; KARIMINEJAD, Ariana; MCDONALD, Marie T.; ARACENA, Mariana I.; LAUSCH, Ekkehart; UNGER, Sheila; SUPERTI-FURGA, Andrea; LU, James T.; COHN, Dan H.; TARTAGLIA, Marco; LEE, Brendan H.; REINHARDT, Dieter P.; CAMPEAU, Philippe M.Fibronectin is a master organizer of extracellular matrices (ECMs) and promotes the assembly of collagens, fibrillin-1, and other proteins. It is also known to play roles in skeletal tissues through its secretion by osteoblasts, chondrocytes, and mesenchymal cells. Spondylo-metaphyseal dysplasias (SMDs) comprise a diverse group of skeletal dysplasias and often manifest as short stature, growth-plate irregularities, and vertebral anomalies, such as scoliosis. By comparing the exomes of individuals with SMD with the radiographic appearance of ""corner fractures'' at metaphyses, we identified three individuals with fibronectin (FN1) variants affecting highly conserved residues. Furthermore, using matching tools and the SkelDys emailing list, we identified other individuals with de novo FN1 variants and a similar phenotype. The severe scoliosis in most individuals and rare developmental coxa vara distinguish individuals with FN1 mutations from those with classical Sutcliffe-type SMD. To study functional consequences of these FN1 mutations on the protein level, we introduced three disease-associated missense variants (p.Cys87Phe [c.260G>T], p.Tyr240Asp [c.718T>G], and p.Cys260Gly [c.778T>G]) into a recombinant secreted N-terminal 70 kDa fragment (rF70K) and the full-length fibronectin (rFN). The wild-type rF70K and rFN were secreted into the culture medium, whereas all mutant proteins were either not secreted or secreted at significantly lower amounts. Immunofluorescence analysis demonstrated increased intracellular retention of the mutant proteins. In summary, FN1 mutations that cause defective fibronectin secretion are found in SMD, and we thus provide additional evidence for a critical function of fibronectin in cartilage and bone.
- Gene expression profile suggesting immunological dysregulation in two Brazilian Bloom's syndrome cases(2020) MONTENEGRO, Marilia M.; QUAIO, Caio R.; PALMEIRA, Patricia; GASPARINI, Yanca; RANGEL-SANTOS, Andreia; DAMASCENO, Julian; NOVAK, Estela M.; GIMENEZ, Thamires M.; YAMAMOTO, Guilherme L.; RONJO, Rachel S.; NOVO-FILHO, Gil M.; CHEHIMI, Samar N.; ZANARDO, Evelin A.; DIAS, Alexandre T.; NASCIMENTO, Amom M.; COSTA, Thais V. M. M.; DUARTE, Alberto J. da S.; COUTINHO, Luiz L.; KIM, Chong A.; KULIKOWSKI, Leslie D.Background Bloom syndrome (BS) is a rare autosomal recessive chromosome instability disorder. The main clinical manifestations are growth deficiency, telangiectasic facial erythema, immunodeficiency, and increased risk to develop neoplasias at early age. Cytogenetic test for sister chromatid exchanges (SCEs) is used as a diagnostic marker for BS. In addition, most patients also present mutations in the & x202f;BLM & x202f;gene, related to defects in the DNA repair mechanism. However, the molecular mechanism behind the pathogenicity of BS is & x202f;still & x202f;not completely understood. Methods We describe two patients confirmed with BS by SCE and molecular analysis. Also, we performed the gene expression profile by the RNA-seq methodology in mRNA transcripts for differential gene expression analysis using as a biological condition for comparison BS versus health controls. Results We detected 216 differentially expressed genes related to immunological pathways such as positive regulation and activation of B cells, immune effector process and absence of difference of DNA repair genes expression. In addition; we also observed differentially expressed genes associated with apoptosis control, such as BCL2L1, CASP7, CDKN1A, E2F2, ITPR, CD274, TNFAIP6, TNFRSF25, TNFRSF13C, and TNFRSF17. Conclusion Our results suggest that the combination of altered expression of genes involved in signaling pathways of immune response and apoptosis control may contribute directly to the main characteristics observed in BS, such as recurrent infections, growth failure, and high risk of cancer. Transcriptome studies of other instability syndromes could allow a more accurate analysis of the relevant gene interactions associated with the destabilization of the genome. This is a first description of the profile of differential gene expression related to immunological aspects detected in patients with BS by RNA-seq.
conferenceObject Severe Osteogenesis imperfecta with oligodontia: think of MESD(2020) MOOSA, S.; YAMAMOTO, G. L.; GARBES, L.; KEUPP, K.; BELEZA-MEIRELES, A.; MORENO, C. A.; VALADARES, E. R.; SOUSA, S. B. de; MAIA, S.; SARAIVA, J.; HONJO, R. S.; KIM, C. A.; MENEZES, H. Cabral de; LAUSCH, E.; LORINI, P. V.; LAMOUNIER JR., A.; CARNIERO, T. C. B.; GIUNTA, C.; ROHRBACH, M.; JANNER, M.; SEMLER, O.; BELEGGIA, F.; LI, Y.; YIGIT, G.; REINTJES, N.; ALTMULLER, J.; NURNBERG, P.; CAVALCANTI, D. P.; ZABEL, B.; WARMAN, M. L.; BERTOLA, D. R.; WOLLNIK, B.; NETZER, C.- Vertebral segmentation defects in a Brazilian cohort: Clinical and molecular analysis focused on spondylocostal dysostosis(2022) LINNENKAMP, Bianca; GIRARDI, Raissa; ROCHA, Leticia; YAMAMOTO, Guilherme; CERONI, Jose Ricardo; MENDES, Antonia Elisabeth Cristhina; HONJO, Rachel; OLIVEIRA, Luiz Antonio; AMEMIYA, Raphael Bruno; QUAIO, Caio; OLIVEIRA FILHO, Joao Bosco de; KIM, Chong Ae; BERTOLA, Debora
- Autosomal-Recessive Mutations in MESD Cause Osteogenesis Imperfecta(2019) MOOSA, Shahida; YAMAMOTO, Guilherme L.; GARBES, Lutz; KEUPP, Katharina; BELEZA-MEIRELES, Ana; MORENO, Carolina Araujo; VALADARES, Eugenia Ribeiro; SOUSA, Sergio B. de; MAIA, Sofia; SARAIVA, Jorge; HONJO, Rachel S.; KIM, Chong Ae; MENEZES, Hamilton Cabral de; LAUSCH, Ekkehart; LORINI, Pablo Villavicencio; LAMOUNIER JR., Arsonval; CARNIERO, Tulio Canella Bezerra; GIUNTA, Cecilia; ROHRBACH, Marianne; JANNER, Marco; SEMLER, Oliver; BELEGGIA, Filippo; LI, Yun; YIGIT, Goekhan; REINTJES, Nadine; ALTMUELLER, Janine; NUERNBERG, Peter; CAVALCANTI, Denise P.; ZABEL, Bernhard; WARMAN, Matthew L.; BERTOLA, Debora R.; WOLLNIK, Bernd; NETZER, ChristianOsteogenesis imperfecta (OI) comprises a genetically heterogeneous group of skeletal fragility diseases. Here, we report on five independent families with a progressively deforming type of OI, in whom we identified four homozygous truncation or frameshift mutations in MESD. Affected individuals had recurrent fractures and at least one had oligodontia. MESD encodes an endoplasmic reticulum (ER) chaperone protein for the canonical Wingless-related integration site (WNT) signaling receptors LRP5 and LRP6. Because complete absence of MESD causes embryonic lethality in mice, we hypothesized that the OI-associated mutations are hypomorphic alleles since these mutations occur downstream of the chaperone activity domain but upstream of ER-retention domain. This would be consistent with the clinical phenotypes of skeletal fragility and oligodontia in persons deficient for LRP5 and LRP6, respectively. When we expressed wild-type (WT) and mutant MESD in HEK293T cells, we detected WT MESD in cell lysate but not in conditioned medium, whereas the converse was true for mutant MESD. We observed that both WT and mutant MESD retained the ability to chaperone LRP5. Thus, 01-associated MESD mutations produce hypomorphic alleles whose failure to remain within the ER significantly reduces but does not completely eliminate LRP5 and LRP6 trafficking. Since these individuals have no eye abnormalities (which occur in individuals completely lacking LRP5) and have neither limb nor brain patterning defects (both of which occur in mice completely lacking LRP6), we infer that bone mass accrual and dental patterning are more sensitive to reduced canonical WNT signaling than are other developmental processes. Biologic agents that can increase LRP5 and LRP6-mediated WNT signaling could benefit individuals with MESD-associated OI.
- Intragenic Deletion in the LIFR Gene in a Long-Term Survivor with Stuve-Wiedemann Syndrome(2015) MARQUES, Julia Hatagami; YAMAMOTO, Guilherme Lopes; TESTAI, Larissa de Cassia; PEREIRA, Alexandre da Costa; KIM, Chong Ae; PASSOS-BUENO, Maria R.; BERTOLA, Debora RomeoStuve-Wiedemann syndrome (SWS, OMIM 601559) is a rare autosomal recessive bent-bone dysplasia, caused by loss-offunction mutations in the leukemia inhibitory factor receptor (LIFR) gene, which usually leads to early death. Only few patients with long-term survival have been described in the literature. We report on a 5-year-old boy from a consanguineous marriage with molecular analysis for the LIFR gene. Sanger and next-generation sequencing (NGS) of LIFR were performed. Copy number variation analysis with NGS showed a novel mutation as the cause for the syndrome: an intragenic homozygous deletion in LIFR, involving exons 1520. Bridging PCR was carried out to confirm the intragenic deletion. This is the first description of a large deletion in LIFR, broadening the spectrum of mutations in SWS. Besides the reported allelic heterogeneity, further studies such as exome sequencing are required to identify a novel gene in order to confirm the locus heterogeneity in SWS. (C) 2015 S. Karger AG, Basel
- Bi-allelic Variants in TONSL Cause SPONASTRIME Dysplasia and a Spectrum of Skeletal Dysplasia Phenotypes(2019) BURRAGE, Lindsay C.; REYNOLDS, John J.; BARATANG, Nissan Vida; PHILLIPS, Jennifer B.; WEGNER, Jeremy; MCFARQUHAR, Ashley; HIGGS, Martin R.; CHRISTIANSEN, Audrey E.; LANZA, Denise G.; SEAVITT, John R.; JAIN, Mahim; LI, Xiaohui; PARRY, David A.; RAMAN, Vandana; CHITAYAT, David; CHINN, Ivan K.; BERTUCH, Alison A.; KARAVITI, Lefkothea; SCHLESINGER, Alan E.; EARL, Dawn; BAMSHAD, Michael; SAVARIRAYAN, Ravi; DODDAPANENI, Harsha; MUZNY, Donna; JHANGIANI, Shalini N.; ENG, Christine M.; GIBBS, Richard A.; BI, Weimin; EMRICK, Lisa; ROSENFELD, Jill A.; POSTLETHWAIT, John; WESTERFIELD, Monte; DICKINSON, Mary E.; BEAUDET, Arthur L.; RANZA, Emmanuelle; HUBER, Celine; CORMIER-DAIRE, Valerie; SHEN, Wei; MAO, Rong; HEANEY, Jason D.; ORANGE, I. Jordan S.; BERTOLA, Debora; YAMAMOTO, Guilherme L.; BARATELA, Wagner Ar; BUTLER, Merlin G.; ALI, Asim; ADELI, Mehdi; COHN, Daniel H.; KRAKOW, Deborah; JACKSON, Andrew P.; LEES, Melissa; OFFIAH, Amaka C.; CARLSTON, Colleen M.; CAREY, John C.; STEWART, Grant S.; BACINO, Carlos A.; CAMPEAU, Philippe M.; LEE, BrendanSPONASTRIME dysplasia is an autosomal-recessive spondyloepimetaphyseal dysplasia characterized by spine (spondylar) abnormalities, midface hypoplasia with a depressed nasal bridge, metaphyseal striations, and disproportionate short stature. Scoliosis, coxa vara, childhood cataracts, short dental roots, and hypogammaglobulinemia have also been reported in this disorder. Although an autosomal-recessive inheritance pattern has been hypothesized, pathogenic variants in a specific gene have not been discovered in individuals with SPONASTRIME dysplasia. Here, we identified bi-allelic variants in TONSL, which encodes the Tonsoku-like DNA repair protein, in nine subjects (from eight families) with SPONASTRIME dysplasia, and four subjects (from three families) with short stature of varied severity and spondylometaphyseal dysplasia with or without immunologic and hematologic abnormalities, but no definitive metaphyseal striations at diagnosis. The finding of early embryonic lethality in a Tonsl(-/-) murine model and the discovery of reduced length, spinal abnormalities, reduced numbers of neutrophils, and early lethality in a tonsl(-/-) zebrafish model both support the hypomorphic nature of the identified TONSL variants. Moreover, functional studies revealed increased amounts of spontaneous replication fork stalling and chromosomal aberrations, as well as fewer camptothecin (CPT)-induced RAD51 foci in subject-derived cell lines. Importantly, these cellular defects were rescued upon re-expression of wild-type (WT) TONSL; this rescue is consistent with the hypothesis that hypomorphic TONSL variants are pathogenic. Overall, our studies in humans, mice, zebrafish, and subject-derived cell lines confirm that pathogenic variants in TONSL impair DNA replication and homologous recombination-dependent repair processes, and they lead to a spectrum of skeletal dysplasia phenotypes with numerous extra-skeletal manifestations.
- Exomic variants of an elderly cohort of Brazilians in the ABraOM database(2017) NASLAVSKY, Michel Satya; YAMAMOTO, Guilherme Lopes; ALMEIDA, Tatiana Ferreira de; EZQUINA, Suzana A. M.; SUNAGA, Daniele Yumi; PHO, Nam; BOZOKLIAN, Daniel; SANDBERG, Tatiana Orli Milkewitz; BRITO, Luciano Abreu; LAZAR, Monize; BERNARDO, Danilo Vicensotto; AMARO JR., Edson; DUARTE, Yeda A. O.; LEBRAO, Maria Lucia; PASSOS-BUENO, Maria Rita; ZATZ, MayanaBrazilians are highly admixed with ancestry from Europe, Africa, America, and Asia and yet still underrepresented in genomic databanks. We hereby present a collection of exomic variants from 609 elderly Brazilians in a census-based cohort (SABE609) with comprehensive phenotyping. Variants were deposited in ABraOM (Online Archive of Brazilian Mutations), a Web-based public database. Population representative phenotype and genotype repositories are essential for variant interpretation through allele frequency filtering; since elderly individuals are less likely to harbor pathogenic mutations for early- and adult-onset diseases, such variant databases are of great interest. Among the over 2.3 million variants from the present cohort, 1,282,008 were high-confidence calls. Importantly, 207,621 variants were absent from major public databases. We found 9,791 potential loss-of-function variants with about 300 mutations per individual. Pathogenic variants on clinically relevant genes (ACMG) were observed in 1.15% of the individuals and were correlated with clinical phenotype. We conducted incidence estimation for prevalent recessive disorders based upon heterozygous frequency and concluded that it relies on appropriate pathogenicity assertion. These observations illustrate the relevance of collecting demographic data from diverse, poorly characterized populations. Census-based datasets of aged individuals with comprehensive phenotyping are an invaluable resource toward the improved understanding of variant pathogenicity.
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