CHONG AE KIM
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Pediatria, Faculdade de Medicina - Docente
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
21 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 21
- Mucolipidosis II and III alpha/beta in Brazil: Analysis of the GNPTAB gene(2013) CURY, G. K.; MATTE, U.; ARTIGALAS, O.; ALEGRA, T.; VELHO, R. V.; SPERB, F.; BURIN, M. G.; RIBEIRO, E. M.; LOURENCO, C. M.; KIM, C. A.; VALADARES, E. R.; GALERA, M. F.; ACOSTA, A. X.; SCHWARTZ, I. V. D.Mucolipidosis H and HI (MLII and MLIII) alpha/beta are rare autosomal recessive lysosomal storage diseases (LSDs) caused by pathogenic variations in the GNPTAB gene. GNPTAB gene codes for the alpha and beta subunits of phosphotransferase, the enzyme responsible for synthesis of the mannose-6-phosphate (M6P) marker that directs lysosomal enzymes to the lysosome. Objectives: The objective of this study is to identify sequence variations of the GNPTAB gene in Brazilian patients with MLII and MLIII alpha/beta. Method: Sequencing of the GNPTAB gene was performed in samples of gDNA extracted from the peripheral blood of patients with MLII/III diagnosed at a national reference center for LSDs. Results: Twelve unrelated patients, from several regions of Brazil, were included in this study. Only one was born of consanguineous parents. All patients were found to carry at least one nonpathogenic variation. Nine causal sequence variations were found: c.242G>T (p.W81L); c.1123C>T (p.R375X); c.1196C>T (p.S399F); c.1208T>C (p.I403T); c.1514G>A (p.C505Y); c.1759C>T (p.R587X); c.2808A>G (p.Y937_M972del, novel mutation); c. 2269_2273delGAAAC (p.E757KfsX2, novel mutation); and c.3503_3504delTC (p.L1168QfsX5). Both pathogenic variations were identified in 8 of 12 patients; in four patients, only one pathogenic variation was identified. Mutation c3503_3504delTC, located in exon 19, was the most frequent pathogenic variation found (n = 11/24 alleles). The deleterious effect of the c.2808A>C mutation on splicing was confirmed by cDNA analysis. Discussion/conclusions: Our findings confirm that the GNPTAB gene presents broad allelic heterogeneity and suggests that, in Brazilian ML II and III patients, screening for mutations should begin at exon 19 of the GNPTAB gene. Further analyses will be conducted on patients in whom both pathogenic mutations have not been found in this study.
- Cri-du-Chat Syndrome: Revealing a Familial Atypical Deletion in 5p(2023) ALMEIDA, Vanessa T.; CHEHIMI, Samar N.; GASPARINI, Yanca; NASCIMENTO, Amom M.; CARVALHO, Gleyson F. S.; MONTENEGRO, Marilia M.; ZANARDO, Evelin Aline; DIAS, Alexandre T.; ASSUNCAO, Nilson A.; KIM, Chong A.; KULIKOWSKI, Leslie D.Introduction: Cri-du-chat syndrome is generally diagnosed when patients present a high-pitched cry at birth, microcephaly, ocular hypertelorism, and prominent nasal bridge. The karyotype is useful to confirm deletions in the short arm of chromosome 5 (5p-) greater than 10 Mb. In cases of smaller deletions, it is necessary to resort to other molecular techniques such as fluorescence in situ hybridization, multiplex ligation-dependent probe amplification (MLPA) or genomic array. Case Presentation: We report a family with an atypical deletion in 5p (mother and 2 children) and variable phenotypes compared with the literature. We applied a P064 MLPA kit to evaluate 5p- in the mother and the 2 children, and we used the Infinium CytoSNP-850K BeadChip genomic array to evaluate the siblings, an 11-year-old boy and a 13-year-old girl, to better define the 5p breakpoints. Both children presented a high-pitched cry at birth, but they did not present any of the typical physical features of 5p- syndrome. The MLPA technique with 5 probes for the 5p region revealed that the patients and their mother presented an atypical deletion with only 4 probes deleted (TERT_ex2, TERT_ex13, CLPTM1L, and IRX4). The genomic array performed in the siblings' samples revealed a 6.2-Mb terminal deletion in 5p15.33p15.32, which was likely inherited from their mother, who presented similar molecular features, seen in MLPA. Discussion: The sparing of the CTNND2 gene, which is associated with cerebral development, in both siblings may explain why these 2 patients had features such as better communication skills which most patients with larger 5p deletions usually do not present. In addition, both patients had smaller deletions than those found in patients with a typical 5p- phenotype. This report demonstrates the utility of genomic arrays as a diagnostic tool to better characterize atypical deletions in known syndromes such as 5p- syndrome, which will allow a better understanding of the genotype-phenotype correlations.
- 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.
- Growth and Clinical Characteristics of Children with Floating-Harbor Syndrome: Analysis of Current Original Data and a Review of the Literature(2020) HOMMA, Thais K.; FREIRE, Bruna L.; HONJO, Rachel; DAUBER, Andrew; FUNARI, Mariana F. A.; LERARIO, Antonio M.; ALBUQUERQUE, Edoarda V. A.; VASQUES, Gabriela A.; BERTOLA, Debora R.; KIM, Chong A.; MALAQUIAS, Alexsandra C.; JORGE, Alexander A. L.Background: Floating-Harbor syndrome (FHS) is a rare condition characterized by dysmorphic facial features, short stature, and expressive language delay. Objective: The aim of this study was to describe a cohort of patients with FHS and review the literature about the response to recombinant human growth hormone (rhGH) therapy. Methods: Anthropometric and laboratory data from 7 patients with FHS were described. The molecular diagnosis was established by multigene analysis. Moreover, we reviewed the literature concerning patients with FHS treated with rhGH. Results: All 7 patients were born small for gestational age. At first evaluation, 6 patients had a height standard deviation score (SDS) <=-2 and 1 had short stature in relation to their target height. Bone age was usually delayed, which rapidly advanced during puberty. Nonspecific skeletal abnormalities were frequently noticed, and normal to elevated plasma IGF-I levels were observed in all except 1 patient with growth hormone deficiency. Information about 20 patients with FHS treated with rhGH was analyzed (4 from our cohort and 16 from the literature). The median height changes during the treatment period (approx. 2.9 years) were 1.1 SDS (range from -0.4 to 3.1). Nontreated patients had an adult height SDS of -4.1 +/- 1.2 (n = 10) versus -2.6 +/- 0.8 SDS (n = 7, p 0.012) for treated patients. Conclusion: We observed a laboratory profile compatible with IGF-1 insensitivity in some patients with FHS. Nevertheless, our study suggests that children with FHS may be considered as candidates for rhGH therapy. Further studies are necessary to establish the real benefit and safety of rhGH therapy in these patients.
- Tegumentary manifestations of Noonan and Noonan-related syndromes(2013) QUAIO, Caio Robledo D'Angioli Costa; ALMEIDA, Tatiana Ferreira de; BRASIL, Amanda Salem; PEREIRA, Alexandre C.; JORGE, Alexander A. L.; MALAQUIAS, Alexsandra C.; KIM, Chong Ae; BERTOLA, Debora RomeoOBJECTIVES: Noonan and Noonan-related syndromes are common autosomal dominant disorders with neuro-cardio-facial-cutaneous and developmental involvement. The objective of this article is to describe the most relevant tegumentary findings in a cohort of 41 patients with Noonan or Noonan-related syndromes and to detail certain aspects of the molecular mechanisms underlying ectodermal involvement. METHODS: A standard questionnaire was administered. A focused physical examination and a systematic review of clinical records was performed on all patients to verify the presence of tegumentary alterations. The molecular analysis of this cohort included sequencing of the following genes in all patients: PTPN1, SOS1, RAF1, KRAS, SHOC2 and BRAF. RESULTS: The most frequent tegumentary alterations were xeroderma (46%), photosensitivity (29%), excessive hair loss (24%), recurrent oral ulcers (22%), curly hair (20%), nevi (17%), markedly increased palmar and plantar creases (12%), follicular hyperkeratosis (12%), palmoplantar hyperkeratosis (10%), cafe-au-lait spots (10%) and sparse eyebrows (7%). Patients with mutations in PTPN11 had lower frequencies of palmar and plantar creases and palmar/plantar hyperkeratosis compared with the other patients. CONCLUSIONS: We observed that patients with mutations in genes directly involved in cell proliferation kinase cascades (SOS1, BRAF, KRAS and RAF1) had a higher frequency of hyperkeratotic lesions compared with patients with mutations in genes that have a more complex interaction with and modulation of cell proliferation kinase cascades (PTPN11).
- Cytogenomic delineation and clinical follow-up of 10 Brazilian patients with Pallister-Killian syndrome(2015) COSTA, Larissa Sampaio de Athayde; ZANDONA-TEIXEIRA, Aline C.; MONTENEGRO, Marilia M.; DIAS, Alexandre T.; DUTRA, Roberta L.; HONJO, Rachel S.; BERTOLA, Debora R.; KULIKOWSKI, Leslie D.; KIM, Chong A.Background: Pallister-Killian syndrome (PKS) is a sporadic genetic disorder caused by the presence of a tissue-specific mosaicism for isochromosome 12p - i(12) (p10) and is characterized by facial dysmorphism including coarse facies, upslanting palpebral fissures, bitemporal alopecia, pigmentary skin anomalies, developmental delay, hypotonia and seizures. Although typical clinical features of PKS commonly exist, clinicians often do not raise the possibility of this diagnosis. Results: We reviewed the medical records of 10 patients with confirmed PKS followed in our service (since 1990 to 2015). Age at diagnosis varied from prenatal to 3 years and clinical features were consistent with those described in the literature. In all patients, peripheral blood karyotypes were normal and cytogenomic study was performed in order to confirm the diagnosis. Three of these patients had PKS diagnosis confirmed by buccal smear MLPA. Conclusion: An early conclusion from our results demonstrated that MLPA on buccal smears is a good and non-invasive method to detect extra copies of 12p and should be considered as the first exam, before a skin biopsy for a fibroblast karyotype is performed.
- Microduplication of the ICR2 Domain at Chromosome 11p15 and Familial Silver-Russell Syndrome(2011) BONALDI, Adriano; MAZZEU, Juliana F.; COSTA, Silvia S.; HONJO, Rachel S.; BERTOLA, Debora R.; ALBANO, Lilian M. J.; FURQUIM, Isabel M.; KIM, Chong A.; VIANNA-MORGANTE, Angela M.Silver-Russell syndrome (SRS) is characterized by severe intrauterine and postnatal growth retardation in association with a typical small triangular face and other variable features. Genetic and epigenetic disturbances are detected in about 50% of the patients. Most frequently, SRS is caused by altered gene expression on chromosome 11p15 due to hypomethylation of the telomeric imprinting center (ICR1) that is present in at least 40% of the patients. Maternally inherited duplications encompassing ICR1 and ICR2 domains at 11p15 were found in a few patients, and a microduplication restricted to ICR2 was described in a single SRS child. We report on a microduplication of the ICR2 domain encompassing the KCNQ1, KCNQ1OT1, and CDKN1C genes in a three-generation family: there were four instances of paternal transmissions of the microduplication from a single male uniformly resulting in normal offspring, and five maternal transmissions, via two clinically normal sisters, with all the children exhibiting SRS. This report provides confirmatory evidence that a microduplication restricted to the ICR2 domain results in SRS when maternally transmitted. (C) 2011 Wiley-Liss, Inc.
- Mowat-Wilson syndrome: neurological and molecular study in seven patients(2015) PAZ, Jose Albino da; KIM, Chong Ae; GOOSSENS, Michael; GIURGEA, Irina; MARQUES-DIAS, Maria JoaquinaObjective: To present a seven-cases serie of Mowat-Wilson syndrome (MWS). Method: All patients with positive mutation for the ZEB2 were evaluated by a geneticist and a neurologist, with clinical and laboratorial characterization. Results: A peculiar facies and mental retardation were present in all patients. The Denver II scale showed intense delay in all aspects, especially fine motor and adaptive. Acquired microcephaly was observed in five patients. Only one patient did not present epilepsy. Epilepsy was focal and predominating in sleep, with status epilepticus in three patients. The initial seizure was associated with fever in most patients (4/6). The EEG showed epileptic focal activity (5/7). The imaging studies revealed total agenesis (4/7) and partial agenesis of the corpus callosum (1/7). Conclusion: Physicians who care for patients with mental retardation and epilepsy should be aware of SMW.
- Abnormal auditory event-related potentials in Williams syndrome*(2021) SILVA, Liliane Aparecida Fagundes; KAWAHIRA, Rachel Sayuri Honjo; KIM, Chong Ae; MATAS, Carla GentileIndividuals with Williams Syndrome (WS) have specific auditory characteristics, including hypoacusis and hyperacusis, and music appreciation skills. Little is known about the functionality of the central auditory nervous system (CANS) for sound processing in WS. Thus, the objective of the present study was to evaluate the functionality of the CANS in individuals with WS, based on auditory event-related potentials, as far as cognitive and behavioral aspects are concerned. The study was carried out with 17 individuals, seven females and ten males, between seven and 17 years old, with WS, and 17 individuals with typical development matched by sex and chronological age to individuals with WS. None of these individuals had middle ear impairment or hearing loss. The subjects were evaluated for intelligence quotient, loudness discomfort level, and auditory event-related potentials with Tone Burst stimuli, on the oddball paradigm; the parents also answered the MTA-SNAP-IV questionnaire. Hyperacusis was found in six WS individuals and two individuals with typical development. In the present study, WS individuals present longer latency and reduced amplitude for P1, N1, N2 and P3 components. These results, suggesting a delay and hypoactive responses of the CANS in this syndrome, that cannot be related to the cognitive or behavioral aspects of these individuals, but it indicates a cortical immaturity to process acoustic stimuli.
- Ocular manifestations of Noonan syndrome(2012) MARIN, Lenina da Rocha Pitta; SILVA, Felipe Theodoro Bezerra Gaspar Carvalho da; SA, Luis Carlos Ferreira de; BRASIL, Amanda Salem; PEREIRA, Alexandre; FURQUIM, Isabel Mosca; KIM, Chong Ae; BERTOLA, Debora RomeoPurpose: To describe the ophthalmological characteristics in a group of Noonan syndrome patients with proven mutations in the PTPN11 gene. Methods: Thirty-five Noonan syndrome patients with PTPN11 gene mutations underwent ophthalmological exams, which consisted of external inspection, slit-lamp biomicroscopy examination and an ophthalmoscopic examination after instillation of 1.0% tropicamide or 1.0% cyclopentolate. Results: All 35 patients had at least one abnormality upon ophthalmological examination. The eyelid and external eye abnormalities were the prevailing features, followed by prominent corneal nerves on slit-lamp exam. Fundus changes were detected in 8% of the subjects, mainly associated with high myopia. No statistically significant differences were observed among the patients presenting specific mutations in the PTPN11 gene. Conclusions: The current study further supports the finding that ocular symptoms account for a large fraction of the clinical manifestations of NS. Additional characteristics are described here. The roles for the various mutations of PTPN11 in ocular development are yet to be established.
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