ALEXANDER AUGUSTO DE LIMA JORGE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina - Docente
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/25 - Laboratório de Endocrinologia Celular e Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/25 - Laboratório de Endocrinologia Celular e Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
- Heterozygous Mutations in Natriuretic Peptide Receptor-B (NPR2) Gene as a Cause of Short Stature in Patients Initially Classified as Idiopathic Short Stature(2013) VASQUES, Gabriela A.; AMANO, Naoko; DOCKO, Ana J.; FUNARI, Mariana F. A.; QUEDAS, Elisangela P. S.; NISHI, Mirian Y.; ARNHOLD, Ivo J. P.; HASEGAWA, Tomonobu; JORGE, Alexander A. L.Context: Based on the stature observed in relatives of patients with acromesomelic dysplasia, type Maroteaux, homozygous for mutations in natriuretic peptide receptor B gene (NPR2), it has been suggested that heterozygous mutations in this gene could be responsible for the growth impairment observed in some children with idiopathic short stature (ISS). Objective: The objective of the study was to investigate the presence of NPR2 mutations in a group of patients with ISS. Patients and Methods: The NPR2 coding region was directly sequenced in 47 independent patients with ISS. The functional consequences of NPR2 nonsynonymous variations were established using in vitro cell-based assays. Results: Three novel heterozygous NPR2 mutations were identified: c.226T>C (p.Ser76Pro), c.788G>C (p.Arg263Pro), and c.2455C>T (p.Arg819Cys). These allelic variants were not found in our controls or in the 1000 Genomes database. In silico analysis suggested that the three missense mutations are probably damaging. All of them were selected for in vitro functional evaluation. Cells transfected with the three mutants failed to produce cyclic GMP after treatment with C-type natriuretic peptide. Cells cotransfected with mutant and wild-type-NPR-B (1:1) showed a significant decrease in cGMP levels after C-type natriuretic peptide stimulation in comparison with cells cotrasnfected with empty vector and wild type, suggesting a dominant-negative effect. These three mutations segregated with short stature phenotype in an autosomal dominant pattern (height SD score ranged from -4.5 to -1.7). One of these patients and two relatives have disproportionate short stature, whereas in another patient a nonspecific skeletal abnormality was observed. All three of these patients were treated with recombinant human GH (33-50 mu g/kg.d) without significant height SD score change during therapy. Conclusions: We identified heterozygous NPR2 mutations in 6% of patients initially classified as ISS. Affected patients have mild and variable degrees of short stature without a distinct phenotype. Heterozygous mutations in NPR2 could be an important cause of nonsyndromic familial short stature.
- Exome Sequencing Reveals the POLR3H Gene as a Novel Cause of Primary Ovarian Insufficiency(2019) FRANCA, Monica M.; HAN, Xingfa; FUNARI, Mariana F. A.; LERARIO, Antonio M.; NISHI, Mirian Y.; FONTENELE, Eveline G. P.; DOMENICE, Sorahia; JORGE, Alexander A. L.; GARCIA-GALIANO, David; ELIAS, Carol F.; MENDONCA, Berenice B.Context: Primary ovarian insufficiency (POI) is a cause of female infertility. However, the genetic etiology of this disorder remains unknown in most patients with POI. Objective: To investigate the genetic etiology of idiopathic POI. Patients and Methods: We performed whole-exome sequencing of 11 families with idiopathic POI. To gain insights into the potential mechanisms associated with this mutation, we generated two mouse lines via clustered regularly interspaced short palindromic repeats/Cas9 technology. Results: A pathogenic homozygous missense mutation (c.149A>G; p.Asp50G ly) in the POLR3H gene in two unrelated families was identified. Pathogenic mutations in this subunit have not been associated with human disorders. Loss-of-function Polr3h mutation in mice caused early embryonic lethality. Mice with homozygous point mutation (Polr3h(D50G)) were viable but showed delayed pubertal development, characterized by late first estrus or preputial separation. The Polr3h(D50G) female and male mice showed decreased fertility later in life, associated with small litter size and increased time to pregnancy or to impregnate a female. Polr3h(D50G) mice displayed decreased expression of ovarian Foxo3a and lower numbers of primary follicles. Conclusion: Our manuscript provides a case of POI caused by missense mutation in POLR3H, expanding the knowledge of molecular pathways of the ovarian function and human infertility. Screening of the POLR3H gene may elucidate POI cases without previously identified genetic causes, supporting approaches of genetic counseling.
- Genetic Evidence of the Association of DEAH-Box Helicase 37 Defects With 46,XY Gonadal Dysgenesis Spectrum(2019) SILVA, Thatiana Evilen da; GOMES, Nathalia Lisboa; LERARIO, Antonio Marcondes; KEEGAN, Catherine Elizabeth; NISHI, Mirian Yumi; CARVALHO, Filomena Marino; VILAIN, Eric; BARSEGHYAN, Hayk; MARTINEZ-AGUAYO, Alejandro; FORCLAZ, Maria Veronica; PAPAZIAN, Regina; PAULA, Leila Cristina Pedroso de; COSTA, Eduardo Correa; CARVALHO, Luciani Renata; JORGE, Alexander Augusto Lima; ELIAS, Felipe Martins; MITCHELL, Rod; COSTA, Elaine Maria Frade; MENDONCA, Berenice Bilharinho; DOMENICE, SorahiaContext: 46,XY Gonadal dysgenesis (GD) is a heterogeneous group of disorders with a wide phenotypic spectrum, including embryonic testicular regression syndrome (ETRS). Objective: To report a gene for 46,XY GD etiology, especially for ETRS. Design: Screening of familial cases of 46,XY GD using whole-exome sequencing and sporadic cases by target gene-panel sequencing. Setting: Tertiary Referral Center for differences/disorders of sex development (DSD). Patients and Interventions: We selected 87 patients with 46,XY DSD (17 familial cases from 8 unrelated families and 70 sporadic cases); 55 patients had GD (among them, 10 patients from 5 families and 8 sporadic cases had ETRS), and 32 patients had 46,XY DSD of unknown etiology. Results: We identified four heterozygous missense rare variants, classified as pathogenic or likely pathogenic in the Asp-Glu-Ala-His-box (DHX) helicase 37 (DHX37) gene in five families (n = 11 patients) and in six sporadic cases. Two variants were recurrent: p.Arg308Gln (in two families and in three sporadic cases) and p.Arg674Trp (in two families and in two sporadic cases). The variants were specifically associated with ETRS (7/14 index cases; 50%). The frequency of rare, predicted-to-be-deleterious DHX37 variants in this cohort (14%) is significantly higher than that observed in the Genome Aggregation Database (0.4%; P < 0.001). Immunohistochemistry analysis in human testis showed that DHX37 is mainly expressed in germ cells at different stages of testis maturation, in Leydig cells, and rarely in Sertoli cells. Conclusion: This strong genetic evidence identifies DHX37 as a player in the complex cascade of male gonadal differentiation and maintenance.
- Contribution of Clinical and Genetic Approaches for Diagnosing 209 Index Cases With 46,XY Differences of Sex Development(2022) GOMES, Nathalia Lisboa; BATISTA, Rafael Loch; NISHI, Mirian Y.; LERARIO, Antonio Marcondes; SILVA, Thatiana E.; NARCIZO, Amanda de Moraes; BENEDETTI, Anna Flavia Figueredo; FUNARI, Mariana Ferreira de Assis; FARIA JUNIOR, Jose Antonio; MORAES, Daniela Rodrigues; QUINTAO, Lia Mesquita Lousada; MONTENEGRO, Luciana Ribeiro; FERRARI, Maria Teresa Martins; JORGE, Alexander A.; ARNHOLD, Ivo J. P.; COSTA, Elaine Maria Frade; DOMENICE, Sorahia; MENDONCA, Berenice BilharinhoContext Massively parallel sequencing (MPS) technologies have emerged as a first-tier approach for diagnosing several pediatric genetic syndromes. However, MPS has not been systematically integrated into the diagnostic workflow along with clinical/biochemical data for diagnosing 46,XY differences of sex development (DSD). Objective To analyze the contribution of phenotypic classification either alone or in association with genetic evaluations, mainly MPS, for diagnosing a large cohort of 46,XY DSD patients. Design/patients 209 nonsyndromic 46,XY DSD index cases from a Brazilian DSD center were included. Patients were initially classified into 3 subgroups according to clinical and biochemical data: gonadal dysgenesis (GD), disorders of androgen secretion/action, and DSD of unknown etiology. Molecular genetic studies were performed by Sanger sequencing and/or MPS. Results Clinical/biochemical classification into either GD or disorders of hormone secretion/action was obtained in 68.4% of the index cases. Among these, a molecular diagnosis was obtained in 36% and 96.5%, respectively. For the remainder 31.6% classified as DSD of clinically unknown etiology, a molecular diagnosis was achieved in 31.8%. Overall, the molecular diagnosis was achieved in 59.3% of the cohort. The combination of clinical/biochemical and molecular approaches diagnosed 78.9% of the patients. Clinical/biochemical classification matched with the genetic diagnosis in all except 1 case. DHX37 and NR5A1 variants were the most frequent genetic causes among patients with GD and DSD of clinical unknown etiology, respectively. Conclusions The combination of clinical/biochemical with genetic approaches significantly improved the diagnosis of 46,XY DSD. MPS potentially decreases the complexity of the diagnostic workup as a first-line approach for diagnosing 46,XY DSD.