BRUNA LUCHEZE FREIRE
Projetos de Pesquisa
Unidades Organizacionais
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- Diagnostic yield of a multigene sequencing approach in children classified as idiopathic short stature(2022) ANDRADE, Nathalia Liberatoscioli Menezes; FUNARI, Mariana Ferreira de Assis; MALAQUIAS, Alexsandra Christianne; COLLETT-SOLBERG, Paulo Ferrez; GOMES, Nathalia L. R. A.; SCALCO, Renata; DANTAS, Naiara Castelo Branco; REZENDE, Raissa C.; TIBURCIO, Angelica M. F. P.; SOUZA, Micheline A. R.; FREIRE, Bruna L.; V, Ana C. Krepischi; LONGUI, Carlos Alberto; LERARIO, Antonio Marcondes; ARNHOLD, Ivo J. P.; JORGE, Alexander A. L.; VASQUES, Gabriela AndradeObjectiveMost children with short stature remain without an etiologic diagnosis after extensive clinical and laboratory evaluation and are classified as idiopathic short stature (ISS). This study aimed to determine the diagnostic yield of a multigene analysis in children classified as ISS. Design and methodsWe selected 102 children with ISS and performed the genetic analysis as part of the initial investigation. We developed customized targeted panel sequencing, including all genes already implicated in the isolated short-stature phenotype. Rare and deleterious single nucleotide or copy number variants were assessed by bioinformatic tools. ResultsWe identified 20 heterozygous pathogenic (P) or likely pathogenic (LP) genetic variants in 17 of 102 patients (diagnostic yield = 16.7%). Three patients had more than one P/LP genetic alteration. Most of the findings were in genes associated with the growth plate differentiation: IHH (n = 4), SHOX (n = 3), FGFR3 (n = 2), NPR2 (n = 2), ACAN (n = 2), and COL2A1 (n = 1) or involved in the RAS/MAPK pathway: NF1 (n = 2), PTPN11 (n = 1), CBL (n = 1), and BRAF (n = 1). None of these patients had clinical findings to guide a candidate gene approach. The diagnostic yield was higher among children with severe short stature (35% vs 12.2% for height SDS <= or > -3; P = 0.034). The genetic diagnosis had an impact on clinical management for four children. ConclusionA multigene sequencing approach can determine the genetic etiology of short stature in up to one in six children with ISS, removing the term idiopathic from their clinical classification.
- Diagnosis of TBC1D32-associated conditions: Expanding the phenotypic spectrum of a complex ciliopathy(2023) HARRIS, Sarah C.; CHONG, Karen; CHITAYAT, David; GILMORE, Kelly L.; JORGE, Alexander A. L.; FREIRE, Bruna L.; LERARIO, Antonio; SHANNON, Patrick; COPE, Heidi; GALLENTINE, William B.; GUYADER, Gwenal Le; BILAN, Frederic; LETARD, Pascaline; DAVIS, Erica E.; VORA, Neeta L.Exome sequencing is a powerful tool in prenatal and postnatal genetics and can help identify novel candidate genes critical to human development. We describe seven unpublished probands with rare likely pathogenic variants or variants of uncertain significance that segregate with recessive disease in TBC1D32, including four fetal probands in three unrelated pedigrees and three pediatric probands in unrelated pedigrees. We also report clinical comparisons with seven previously published patients. Index probands were identified through an ongoing prenatal exome sequencing study and through an online data sharing platform (Gene Matcher (TM)). A literature review was also completed. TBC1D32 is involved in the development and function of cilia and is expressed in the developing hypothalamus and pituitary gland. We provide additional data to expand the phenotype correlated with TBC1D32 variants, including a severe prenatal phenotype associated with life-limiting congenital anomalies.
- Variants in 46,XY DSD-Related Genes in Syndromic and Non-Syndromic Small for Gestational Age Children with Hypospadias(2022) BRAGA, B. L.; GOMES, N. L.; NISHI, M. Y.; FREIRE, B. L.; BATISTA, R. L.; FARIA JUNIOR, J. A. D.; FUNARI, M. F. A.; BENEDETTI, A. F. F.; NARCIZO, A. De Moraes; CARDOSO, L. Cavalca; LERARIO, A. M.; GUERRA-JUNIOR, G.; COSTA, E. M. F.; DOMENICE, S.; JORGE, A. A. L.; MENDONCA, B. B.Hypospadias is a common congenital disorder of male genital formation. Children born small for gestational age (SGA) present a high frequency of hypospadias of undetermined etiology. No previous study investigated the molecular etiology of hypospadias in boys born SGA using massively parallel sequencing. Our objective is to report the genetic findings of a cohort of patients born SGA with medium or proximal hypospadias. We identified 46 individuals with this phenotype from a large cohort of 46,XY DSD patients, including 5 individuals with syndromic features. DNA samples from subjects were studied by either whole exome sequencing or target gene panel approach. Three of the syndromic patients have 5 main clinical features of Silver-Russell syndrome (SRS) and were first studied by MLPA. Among the syndromic patients, loss of DNA methylation at the imprinting control region H19/IGF2 was identified in 2 individuals with SRS clinical diagnosis. Two novel pathogenic variants in compound heterozygous state were identified in the CUL7 gene establishing the diagnosis of 3M syndrome in one patient, and a novel homozygous variant in TRIM37 was identified in another boy with Mulibrey nanism phenotype. Among the non-syndromic subjects, 7 rare heterozygous variants were identified in 6 DSD-related genes. However, none of the variants found can explain the phenotype by themselves. In conclusion, a genetic defect that clarifies the etiology of hypospadias was not found in most of the non-syndromic SGA children, supporting the hypothesis that multifactorial causes, new genes, and/or unidentified epigenetic defects may have an influence in this condition.
- A thermosensitive PCNA allele underlies an ataxia- telangiectasia-like disorder(2023) MAGRINO, Joseph; MUNFORD, Veridiana; MARTINS, Davi Jardim; HOMMA, Thais K.; PAGE, Brendan; GAUBITZ, Christl; FREIRE, Bruna L.; LERARIO, Antonio M.; VILAR, Juliana Brandstetter; AMORIN, Antonio; LEAO, Emilia K. E.; KOK, Fernand; MENCK, Carlos F. M.; JORGE, Alexander A. L.; KELCH, Brian A.Proliferating cell nuclear antigen (PCNA) is a sliding clamp protein that coordinates DNA replication with various DNA maintenance events that are critical for human health. Recently, a hypomorphic homozygous serine to isoleucine (S228I) substitu-tion in PCNA was described to underlie a rare DNA repair dis-order known as PCNA-associated DNA repair disorder (PARD). PARD symptoms range from UV sensitivity, neurodegeneration, telangiectasia, and premature aging. We, and others, previously showed that the S228I variant changes the protein-binding pocket of PCNA to a conformation that impairs interactions with specific partners. Here, we report a second PCNA substitution (C148S) that also causes PARD. Unlike PCNA-S228I, PCNA-C148S has WT-like structure and affinity toward partners. In contrast, both disease-associated variants possess a thermostability defect. Furthermore, patient-derived cells homozygous for the C148S allele exhibit low levels of chromatin-bound PCNA and display temperature-dependent phenotypes. The stability defect of both PARD variants indicates that PCNA levels are likely an important driver of PARD disease. These results significantly advance our understanding of PARD and will likely stimulate additional work focused on clinical, diagnostic, and therapeutic aspects of this severe disease.
- Burden of Rare Copy Number Variants in Microcephaly: A Brazilian Cohort of 185 Microcephalic Patients and Review of the Literature(2024) TOLEZANO, Giovanna Cantini; BASTOS, Giovanna Civitate; COSTA, Silvia Souza da; FREIRE, Bruna Lucheze; HOMMA, Thais Kataoka; HONJO, Rachel Sayuri; YAMAMOTO, Guilherme Lopes; PASSOS-BUENO, Maria Rita; KOIFFMANN, Celia Priszkulnik; KIM, Chong Ae; VIANNA-MORGANTE, Angela Maria; JORGE, Alexander Augusto de Lima; BERTOLA, Debora Romeo; ROSENBERG, Carla; KREPISCHI, Ana Cristina VictorinoMicrocephaly presents heterogeneous genetic etiology linked to several neurodevelopmental disorders (NDD). Copy number variants (CNVs) are a causal mechanism of microcephaly whose investigation is a crucial step for unraveling its molecular basis. Our purpose was to investigate the burden of rare CNVs in microcephalic individuals and to review genes and CNV syndromes associated with microcephaly. We performed chromosomal microarray analysis (CMA) in 185 Brazilian patients with microcephaly and evaluated microcephalic patients carrying < 200 kb CNVs documented in the DECIPHER database. Additionally, we reviewed known genes and CNV syndromes causally linked to microcephaly through the PubMed, OMIM, DECIPHER, and ClinGen databases. Rare clinically relevant CNVs were detected in 39 out of the 185 Brazilian patients investigated by CMA (21%). In 31 among the 60 DECIPHER patients carrying < 200 kb CNVs, at least one known microcephaly gene was observed. Overall, four gene sets implicated in microcephaly were disclosed: known microcephaly genes; genes with supporting evidence of association with microcephaly; known macrocephaly genes; and novel candidates, including OTUD7A, BBC3, CNTN6, and NAA15. In the review, we compiled 957 known microcephaly genes and 58 genomic CNV loci, comprising 13 duplications and 50 deletions, which have already been associated with clinical findings including microcephaly. We reviewed genes and CNV syndromes previously associated with microcephaly, reinforced the high CMA diagnostic yield for this condition, pinpointed novel candidate loci linked to microcephaly deserving further evaluation, and provided a useful resource for future research on the field of neurodevelopment.