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.
- A Genome-Wide Pharmacogenetic Study of Growth Hormone Responsiveness(2020) DAUBER, Andrew; MENG, Yan; AUDI, Laura; VEDANTAM, Sailaja; WEAVER, Benjamin; CARRASCOSA, Antonio; ALBERTSSON-WIKLAND, Kerstin; RANKE, Michael B.; JORGE, Alexander A. L.; CARA, Jose; WAJNRAJCH, Michael P.; LINDBERG, Anders; CAMACHO-HUBNER, Cecilia; HIRSCHHORN, Joel N.Context: Individual patients vary in their response to growth hormone (GH). No large-scale genome-wide studies have looked for genetic predictors of GH responsiveness. Objective: To identify genetic variants associated with GH responsiveness. Design: Genome-wide association study (GWAS). Setting: Cohorts from multiple academic centers and a clinical trial. Patients: A total of 614 individuals from 5 short stature cohorts receiving GH: 297 with idiopathic short stature, 276 with isolated GH deficiency, and 65 born small for gestational age. Intervention: Association of more than 2 million variants was tested. Main Outcome Measures: Primary analysis: individual single nucleotide polymorphism (SNP) association with first-year change in height standard deviation scores. Secondary analyses: SNP associations in clinical subgroups adjusted for clinical variables; association of polygenic score calculated from 697 genome-wide significant height SNPs with GH responsiveness. Results: No common variant associations reached genome-wide significance in the primary analysis. The strongest suggestive signals were found near the B4GALT4 and TBCE genes. After meta-analysis including replication data, signals at several loci reached or retained genomewide significance in secondary analyses, including variants near ST3GAL6. There was no significant association with variants previously reported to be associated with GH response nor with a polygenic predicted height score. Conclusions: We performed the largest GWAS of GH responsiveness to date. We identified 2 loci with a suggestive effect on GH responsiveness in our primary analysis and several genomewide significant associations in secondary analyses that require further replication. Our results are consistent with a polygenic component to GH responsiveness, likely distinct from the genetic regulators of adult height.
- Response to Letter to the Editor: ""A Genome-Wide Pharmacogenetic Study of Growth Hormone Responsiveness""(2021) HIRSCHHORN, Joel N.; DAUBER, Andrew; AUDI, Laura; VEDANTAM, Sailaja; RANKE, Michael B.; JORGE, Alexander A. L.; LINDBERG, Anders; CAMACHO-HUBNER, Cecilia; WAJNRAJCH, Michael P.
- The Interactive Effect of GHR-Exon 3 and -202 A/C IGFBP3 Polymorphisms on rhGH Responsiveness and Treatment Outcomes in Patients with Turner Syndrome(2012) BRAZ, Adriana F.; COSTALONGA, Everlayny F.; MONTENEGRO, Luciana R.; TRARBACH, Ericka B.; ANTONINI, Sonir R. R.; MALAQUIAS, Alexsandra C.; RAMOS, Ester S.; MENDONCA, Berenice B.; ARNHOLD, Ivo J. P.; JORGE, Alexander A. L.Context: There is great interindividual variability in the response to recombinant human (rh) GH therapy in patients with Turner syndrome (TS). Ascertaining genetic factors can improve the accuracy of growth response predictions. Objective: The objective of the study was to assess the individual and combined influence of GHR-exon 3 and -202 A/C IGFBP3 polymorphisms on the short-and long-term outcomes of rhGH therapy in patients with TS. Design and Patients: GHR-exon 3 and -202 A/C IGFBP3 genotyping (rs2854744) was correlated with height data of 112 patients with TS who remained prepubertal during the first year of rhGH therapy and 65 patients who reached adult height after 5 +/- 2.5 yr of rhGH treatment. Main Outcome Measures: First-year growth velocity and adult height were measured. Results: Patients carrying at least one GHR-d3 or -202 A-IGFBP3 allele presented higher mean first-year growth velocity and achieved taller adult heights than those homozygous for GHR-fl or -202 C-IGFBP3 alleles, respectively. The combined analysis of GHR-exon 3 and -202 A/C IGFBP3 genotypes showed a clear nonadditive epistatic influence on adult height of patients with TS treated with rhGH (GHR-exon 3 alone, R-2 = 0.27; -202 A/C IGFBP3, R-2 = 0.24; the combined genotypes, R-2 = 0.37 at multiple linear regression). Together with clinical factors, these genotypes accounted for 61% of the variability in adult height of patients with TS after rhGH therapy. Conclusion: Homozygosity for the GHR-exon3 full-length allele and/or the -202C-IGFBP3 allele are associated with less favorable short-and long-term growth outcomes after rhGH treatment in patients with TS.