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1.
Arch. argent. pediatr ; 119(4): e340-e344, agosto 2021. tab, ilus
Article in Spanish | LILACS, BINACIS | ID: biblio-1281780

ABSTRACT

La acrodisostosis es una displasia esquelética rara, de herencia autosómica dominante, que se caracteriza por la presencia de disostosis facial y periférica, talla baja y diferentes grados de obesidad. La acrodisostosis de tipo 1, secundaria a la mutación heterocigota en el gen PRKAR1A (17q24.2), se caracteriza por la asociación de resistencia hormonal múltiple con anomalías esqueléticas. Su incidencia está infradiagnosticada debido a que comparte rasgos clínicos y de laboratorio con otras entidades como el seudohipoparatiroidismo. Presentamos el caso de una niña de 8 años, con acrodisostosis tipo 1, confirmada mediante estudio genético. Además del fenotipo característico descrito, la talla baja y la resistencia hormonal, la paciente presentó una afectación progresiva de la función pulmonar: un patrón pulmonar obstructivo no reversible. En la literatura revisada, no se han encontrado otros casos que describan esta asociación entre acrodisostosis y afectación respiratoria.


Acrodysostosis is a rare skeletal displasia, of autosomal dominant inheritance, characterized by the presence of facial and peripheral dysostosis, short stature and obesity. Type 1 acrodysostosis is secondary to a mutation in the PRKAR1A (17q24.2) gene, which results in multi hormonal resistance and skeletal anomalities. This syndrome is under-diagnosed as it shares analytical and clinical characteristics with other entities, such as pseudohypoparathyroidism. We report the case of an eight-year-old girl with genetically confirmed type 1 acrodysostosis. In addition to the characteristic phenotype described, the short stature and the hormonal resistance, the patient suffered a progressive lung function deterioration: an irreversible pulmonary obstructive pattern. We have not found in previous literature cases reporting an association between acrodysostosis and lung function impairement.


Subject(s)
Humans , Female , Child , Osteochondrodysplasias/complications , Dysostoses/complications , Lung Diseases, Obstructive/complications , Osteochondrodysplasias/genetics , Osteochondrodysplasias/diagnostic imaging , Spirometry , Diagnosis, Differential , Dysostoses/genetics , Dysostoses/diagnostic imaging , Dyspnea/complications , Mutation/genetics
2.
Electron. j. biotechnol ; 52: 59-66, July. 2021. ilus, tab
Article in English | LILACS | ID: biblio-1283592

ABSTRACT

BACKGROUND: Many human genetic diseases arise from point mutations. These genetic diseases can theoretically be corrected through gene therapy. However, gene therapy in clinical application is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes and the ideal approaches to correct these mutations are base editing. These CRISPR-Cas9-mediated base editing does not leave any footprint in genome and does not require donor DNA sequences for homologous recombination. These base editing methods have been successfully applied to cultured mammalian cells with high precision and efficiency, but BE4 has not been confirmed in mice. Animal models are important for dissecting pathogenic mechanism of human genetic diseases and testing of base correction efficacy in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U). RESULTS: In this study, BE4 system was tested in cells to inactivate GFP gene and in mice to introduce single-base substitution that would lead to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted potential off-target sites. CONCLUSIONS: Results confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.


Subject(s)
Animals , Mice , Adenosine Deaminase , Cytosine , CRISPR-Cas Systems , Gene Editing/methods , Base Sequence , Blotting, Western , Models, Animal , Real-Time Polymerase Chain Reaction , Mutation
4.
Article in Spanish | LILACS, CUMED | ID: biblio-1289427

ABSTRACT

Introducción: La leucemia linfoide crónica es un trastorno linfoproliferativo caracterizado por la acumulación de linfocitos pequeños de aspecto maduro en sangre periférica, médula ósea y tejidos linfoides con un período de vida prolongado. Presenta una gran variabilidad clínica y genética. Objetivo: Describir los aspectos citogenéticos y moleculares de la leucemia linfoide crónica. Métodos: Se realizó revisión de la literatura en inglés y español, a través del sitio web PubMed y el motor de búsqueda Google académico, de artículos publicados en los últimos 5 años. Se hizo un análisis y resumen de la bibliografía revisada. Desarrollo: En la leucemia linfoide crónica están presentes alteraciones citogenéticas frecuentes como la deleción de los cromosomas 13q, 11q y 17p, así como la trisomía 12, que unido al conocimiento del estado mutacional del gen de la región variable de la cadena pesada de la inmunoglobulina, y otras mutaciones somáticas en diferentes genes, así como a variables clínicas y de laboratorio permiten la estratificación pronóstica de los pacientes. Conclusiones: El diagnóstico a través de los estudios citogenéticos convencionales estimulados con mitógenos, la hibridación in situ por fluorescencia y la secuenciación génica permite una mayor comprensión de la biología de la enfermedad, así como tomar decisiones terapéuticas más personalizadas(AU)


Introduction: Chronic B lymphoid leukemia is a lymphoproliferative disorder characterized by the accumulation of small, mature-looking lymphocytes in peripheral blood, bone marrow and lymphoid tissues with a long life span. It has great clinical and genetic variability. Objective: To describe the cytogenetic and molecular aspects of the disease. Methods: A review of the literature in English and in Spanish was carried out, in the PubMed website and using the search engine of Google Scholar, for articles published in the last five years. We performed analysis and summary of the reviewed bibliography. Development: In chronic lymphoid leukemia, frequent cytogenetic alterations are present such as deletion of chromosomes 13q, 11q and 17p, as well as trisomy 12, which together with the knowledge of the mutational status of the gene for the variable region of the immunoglobulin heavy chain and other somatic mutations in different genes, as well as clinical and laboratory variables allows prognostic stratification of patients. Conclusions: Diagnosis through conventional mitogen-stimulated cytogenetic studies, fluorescence in situ hybridization and gene sequencing allow a better understanding of the biology of the disease, as well as making more personalized therapeutic decisions(AU)


Subject(s)
Biology , Genetic Therapy , Leukemia, Lymphoid/genetics , In Situ Hybridization , Cytogenetics , Lymphoproliferative Disorders , Mutation
6.
Vive (El Alto) ; 4(10): 128-142, abr. 2021. ilus., tab.
Article in Spanish | LILACS | ID: biblio-1292927

ABSTRACT

INTRODUCCIÓN: la Leucemia Mieloide Aguda es la neoplasia hematológica más común, caracterizada por una proliferación incontrolada de células madre hematopoyéticas. La mutación FLT3/ITD se presenta en aproximadamente el 30% de todos los pacientes con ésta patología, se asocia con mayor riesgo de recaída y menor supervivencia. El FLT3-ITD puede usarse como un factor pronóstico de la gravedad de ésta patología, importante para predecir los resultados clínicos en pacientes con LMA. OBJETIVO: el objetivo de este estudio fue relacionar la mutación FLT3/ITD con variables hematológicas y clínicas en pacientes diagnosticados con Leucemia Mieloide Aguda atendidos en la Sociedad de Lucha contra el Cáncer (SOLCA) de la ciudad de Cuenca, periodo 2013 ­2020. MÉTODOS: se obtuvieron los datos a partir de registros secundarios registrados una base de datos del hospital, el universo de la muestra lo constituyeron 63 pacientes, diagnosticados con LMA, se les analizó la mutación FLT3/ITD por PCR Convencional. RESULTADOS: se encontró la presencia de la mutación en un 9.5% y una asociación significativamente estadística con alteraciones hematológicas relacionados con niveles de hemoglobina anormal (p=0,037) y ratio 6,63 y LDH elevada en 1,21 veces (p=0,024); recuento elevado de leucocitos y blastos (p=0,031). Los individuos portadores de la mutación se presentó con mayor incidencia en el sexo masculino y grupo etario adulto mediano (45-64 años). CONCLUSIONES: la literatura internacional afirma que la mutación FLT3/ITD en un importante marcador pronóstico; debido a su baja frecuencia, no se pudo determinar una relación estadísticamente significativa con otras variables clínicas en este estudio.(AU)


INTRODUCTION: acute Myeloid Leukemia is the most common hematological neoplasm, characterized by an uncontrolled proliferation of hematopoietic stem cells. The FLT3 / ITD mutation occurs in approximately 30% of all patients with this pathology, it is associated with a higher risk of relapse and lower survival. FLT3-ITD can be used as a poor prognostic factor, important for predicting clinical outcomes in patients with AML. OBJECTIVE: the objective of this study was to characterize the FLT3 / ITD mutation and its relationship with hematological and clinical variables in patients diagnosed with Acute Myeloid Leukemia treated at SOLCA in the city of Cuenca, period 2013-2020. METHODS: data were obtained from secondary records in a hospital database, the universe of the sample was made up of 63 patients, diagnosed with AML, and the FLT3 / ITD mutation was analyzed by Conventional PCR. RESULTS: the presence of the mutation was found in 9.5% and a statistically significantly association with hematological alterations related to abnormal hemoglobin levels (p = 0.037) and ratio 6.63 and LDH elevated in 1.21 times (p =0.024); Elevated leukocyte and blast count (p = 0.031). Individuals carrying the mutation had a higher incidence in males and in the middle adult age group (45-64 years). CONCLUSIONS: the international literature affirms that the FLT3 / ITD mutation is an important prognostic marker; Due to its low frequency, it was not possible to determine a statistically significant relationship with other clinical variables in our study, for which it is suggested to expand the unirverse of the sample.(AU)


INTRODUÇÃO: a Leucemia Mielóide Aguda é a malignidade hematológica mais comum, caracterizada pela proliferação descontrolada de células-tronco hematopoiéticas. A mutação FLT3/ITD está presente em aproximadamente 30% de todos os pacientes com esta patologia, e está associada a um maior risco de recaída e menor sobrevida. O FLT3-ITD pode ser usado como um fator prognóstico para a gravidade desta patologia, importante para prever os resultados clínicos em pacientes com LMA. OBJETIVO: o objetivo deste estudo foi relacionar a mutação FLT3/ITD com variáveis hematológicas e clínicas em pacientes diagnosticados com leucemia mielóide aguda tratados na Sociedade de Luta contra o Câncer (SOLCA) na cidade de Cuenca, período 2013 - 202020. Métodos. Os dados foram obtidos de registros secundários registrados em um banco de dados hospitalar, o universo da amostra consistiu de 63 pacientes diagnosticados com AML, eles foram analisados para a mutação FLT3/ITD por PCR convencional. RESULTADOS: a presença da mutação foi encontrada em 9,5% e uma associação estatística significativa com alterações hematológicas relacionadas a níveis anormais de hemoglobina (p=0,037) e relação 6,63 e LDH elevada em 1,21 vezes (p=0,024); contagem elevada de leucócitos e explosões (p=0,031). Os individuos portadores da mutação ocorreram com maior incidência no sexo masculino e na faixa etária média adulta (45-64 anos). CONCLUSÕES: a literatura internacional afirma que a mutação FLT3/ITD em um marcador prognóstico importante; devido a sua baixa freqüência, uma relação estatisticamente significativa com outras variáveis clínicas não pôde ser determinada neste estudo.(AU)


Subject(s)
Humans , Male , Female , Leukemia, Myeloid, Acute , Polymerase Chain Reaction , Mutation , Neoplasms
9.
Washington; Organización Panamericana de la Salud; mar. 24, 2021. 9 p.
Non-conventional in Spanish | LILACS | ID: biblio-1151432

ABSTRACT

A la fecha, 141 los países/territorios han detectado casos de infección por alguna de las tres variantes de preocupación (VOC) reconocidas actualmente por la Organización Mundial de la Salud (OMS). De ese total, 32 países/territorios corresponden a la Región de las Américas.


Subject(s)
Pneumonia, Viral/genetics , DNA, Viral/genetics , Coronavirus Infections/genetics , Pandemics/prevention & control , Epidemiological Monitoring , Betacoronavirus/immunology , Mutation , Americas/epidemiology
10.
Rev. bras. cir. cardiovasc ; 36(1): 112-115, Jan.-Feb. 2021. tab, graf
Article in English | LILACS | ID: biblio-1155784

ABSTRACT

Abstract A 71 year-old male with a history of multiple excisions of an initial Clark's level V melanoma of the breast followed by combined radiation and interferon treatment, as well as a recurrence, 3 years later, of a BRAF-positive tumor of the shoulder, with subsequent therapy with dabrafenib and trametinib, presented again with progressive intracardiac masses causing significant right ventricular outflow obstruction. Additionally, the patient complained of dyspnea and fatigue on exertion, thus he was scheduled for surgical resection.


Subject(s)
Humans , Male , Aged , Skin Neoplasms/surgery , Heart Neoplasms/surgery , Heart Neoplasms/diagnostic imaging , Melanoma/surgery , Melanoma/drug therapy , Mutation , Neoplasm Recurrence, Local
11.
Goiânia; SES-GO; 18 jan. 2021. 1-5 p. mapas.
Non-conventional in Portuguese | LILACS, ColecionaSUS, CONASS, SES-GO | ID: biblio-1146977

ABSTRACT

A pandemia desencadeada pela disseminação do novo coronavírus tornou-se uma grande e constante preocupação para a população, governos e serviços de saúde do mundo inteiro. Devido aos inúmeros impactos que atingiram diferentes setores da sociedade, todos os temas referentes ao SARS-CoV-2 atraem muita atenção e, recentemente, o assunto que trata das novas variantes deste agente etiológico tornou-se bastante frequente em diferentes veículos de comunicação. Os vírus são organismos que constantemente sofrem mudanças por meio de mutações e, portanto, o surgimento de novas variantes é um evento esperado


Subject(s)
Humans , Male , Female , Coronavirus Infections/transmission , Coronavirus Infections/virology , Mutation/immunology
12.
Med. lab ; 25(1): 441-447, 2021. tabs, ilus
Article in Spanish | LILACS | ID: biblio-1292917

ABSTRACT

El síndrome CHARGE es un trastorno genético raro que generalmente se diagnostica durante el período prenatal o neonatal, con la identificación de numerosas anomalías dismórficas y congénitas, como coloboma, defectos cardiacos, atresia de coanas, retraso del crecimiento, hipogonadismo y defectos auditivos, con una incidencia de 1 por cada 12.000 a 15.000 nacidos vivos. Presenta un patrón de herencia autosómico dominante, y entre el 60% y el 70% de los casos se deben a mutaciones que alteran la secuencia del gen CHD7 en el cromosoma 8, las cuales en su mayoría (>90%) son mutaciones de novo. Se describe el caso de una paciente de 6 años con sospecha de síndrome de malformaciones múltiples, que presentó al examen físico talla baja, pabellones de baja implantación, frente amplia, antecedentes de atresia esofágica, hipoacusia neurosensorial, coloboma y riñón en herradura, los cuales son criterios mayores y menores para el diagnóstico clínico de la entidad. Posteriormente, se realizó secuenciación del exoma completo, detectándose alteración del gen CHD7, que confirmó el diagnóstico de síndrome CHARGE. Se debe tener presente que, aunque la prueba molecular confirma el diagnóstico, un gran porcentaje de los pacientes con diagnóstico clínico de síndrome CHARGE no presentan alteraciones en la secuencia de este gen; por lo tanto, el diagnóstico clínico, basado en las alteraciones fenotípicas, continúa demostrando su relevancia


CHARGE syndrome is a rare genetic disorder, which is usually diagnosed during the prenatal or neonatal period with the identification of numerous dysmorphic and congenital abnormalities, characterized by coloboma, heart defects, choanal atresia, retarded growth and development, hypogonadism, and hearing defects, with an incidence of 1 in every 12,000 to 15,000 live births. It has an autosomal dominant inheritance pattern, and between 60% and 70% of cases are caused by mutations in the CHD7 gene at chromosome 8, with the majority (>90%) of mutations occurring de novo. The case of a 6-year-old patient with a multiple malformation syndrome is described, who presented during the physical examination with short stature, ear abnormalities, prominent forehead, a history of esophageal atresia, sensorineural hearing loss, coloboma and horseshoe kidney, which are major and minor criteria for the clinical diagnosis of this condition. Subsequently, complete exome sequencing was performed, detecting a mutation in the CHD7 gene, that confirmed the diagnosis of CHARGE syndrome. It should be noted that although the molecular test confirms the diagnosis, a large percentage of patients with a clinical diagnosis of CHARGE syndrome do not have mutations in this gene sequence; therefore, clinical diagnosis, based on phenotypic features, continues demonstrating its relevance


Subject(s)
CHARGE Syndrome , Genetics , Mutation
13.
Clinics ; 76: e2052, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153974

ABSTRACT

OBJECTIVES: Single nucleotide variants (SNVs) are the most common type of genetic variation among humans. High-throughput sequencing methods have recently characterized millions of SNVs in several thousand individuals from various populations, most of which are benign polymorphisms. Identifying rare disease-causing SNVs remains challenging, and often requires functional in vitro studies. Prioritizing the most likely pathogenic SNVs is of utmost importance, and several computational methods have been developed for this purpose. However, these methods are based on different assumptions, and often produce discordant results. The aim of the present study was to evaluate the performance of 11 widely used pathogenicity prediction tools, which are freely available for identifying known pathogenic SNVs: Fathmn, Mutation Assessor, Protein Analysis Through Evolutionary Relationships (Phanter), Sorting Intolerant From Tolerant (SIFT), Mutation Taster, Polymorphism Phenotyping v2 (Polyphen-2), Align Grantham Variation Grantham Deviation (Align-GVGD), CAAD, Provean, SNPs&GO, and MutPred. METHODS: We analyzed 40 functionally proven pathogenic SNVs in four different genes associated with differences in sex development (DSD): 17β-hydroxysteroid dehydrogenase 3 (HSD17B3), steroidogenic factor 1 (NR5A1), androgen receptor (AR), and luteinizing hormone/chorionic gonadotropin receptor (LHCGR). To evaluate the false discovery rate of each tool, we analyzed 36 frequent (MAF>0.01) benign SNVs found in the same four DSD genes. The quality of the predictions was analyzed using six parameters: accuracy, precision, negative predictive value (NPV), sensitivity, specificity, and Matthews correlation coefficient (MCC). Overall performance was assessed using a receiver operating characteristic (ROC) curve. RESULTS: Our study found that none of the tools were 100% precise in identifying pathogenic SNVs. The highest specificity, precision, and accuracy were observed for Mutation Assessor, MutPred, SNP, and GO. They also presented the best statistical results based on the ROC curve statistical analysis. Of the 11 tools evaluated, 6 (Mutation Assessor, Phanter, SIFT, Mutation Taster, Polyphen-2, and CAAD) exhibited sensitivity >0.90, but they exhibited lower specificity (0.42-0.67). Performance, based on MCC, ranged from poor (Fathmn=0.04) to reasonably good (MutPred=0.66). CONCLUSION: Computational algorithms are important tools for SNV analysis, but their correlation with functional studies not consistent. In the present analysis, the best performing tools (based on accuracy, precision, and specificity) were Mutation Assessor, MutPred, and SNPs&GO, which presented the best concordance with functional studies.


Subject(s)
Humans , Computational Biology , Mutation, Missense/genetics , Virulence , Polymorphism, Single Nucleotide , Sexual Development , Mutation
14.
Clinics ; 76: e2251, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153972

ABSTRACT

OBJECTIVES: Lung cancer is the leading cause of cancer-related deaths worldwide. However, factors associated with the survival of patients with advanced non-small-cell lung cancer (NSCLC) who received only hospice care are largely unclear. In this study, we aimed to determine the prognostic factors correlated with survival in patients with advanced NSCLC who had undergone hospice care only. METHODS: A total of 102 patients with recurrent stage III/IV NSCLC after traditional treatment failure were investigated. Survival was measured from the date of enrollment to December 2019 or the time of death. Tumor tissues were collected, and DNA sequencing was performed to identify somatic mutations. Data on clinical factors of patients were collected and analyzed by univariate and multivariate analyses. Overall survival analysis was conducted using the Kaplan-Meier method. RESULTS: The 6-month, 1-year, and 2-year overall survival rates of the 102 patients with metastatic NSCLC were 17.65%, 3.92%, and 0.98%, respectively. The median overall survival of the 102 patients was 3.15 months. Tumor location in the peripheral lung, epidermal growth factor receptor (EGFR) inhibitor history, low tumor mutation load, adenocarcinoma, and poor performance status score were associated with prolonged survival compared with tumor location in the central lung, no EGFR inhibitor history, high tumor mutation load, squamous cell carcinoma, and good performance status score (p=0.045, p=0.003, p=0.045, p=0.021, and p=0.0003, respectively). CONCLUSIONS: EGFR inhibitor treatment history and tumor mutation load are risk factors for the overall survival of patients with stage III/IV NSCLC who have undergone only hospice care. These results provide a critical clinical basis for further study of nontraditional anti-tumor responses induced by EGFR inhibitors.


Subject(s)
Humans , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/drug therapy , Prognosis , Retrospective Studies , Protein Kinase Inhibitors/therapeutic use , ErbB Receptors/genetics , Mutation , Neoplasm Staging
15.
Clinics ; 76: e2324, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153955

ABSTRACT

OBJECTIVES: The present study aimed to contribute to the catalog of genetic mutations involved in the carcinogenic processes of uterine sarcomas (USs) and carcinosarcomas (UCSs), which may assist in the accurate diagnosis of, and selection of treatment regimens for, these conditions. METHODS: We performed gene-targeted next-generation sequencing (NGS) of 409 cancer-related genes in 15 US (7 uterine leiomyosarcoma [ULMS], 7 endometrial stromal sarcoma [ESS], 1 adenosarcoma [ADS]), 5 UCS, and 3 uterine leiomyoma (ULM) samples. Quality, frequency, and functional filters were applied to select putative somatic variants. RESULTS: Among the 23 samples evaluated in this study, 42 loss-of-function (LOF) mutations and 111 missense mutations were detected, with a total of 153 mutations. Among them, 66 mutations were observed in the Catalogue of Somatic Mutations in Cancer (COSMIC) database. TP53 (48%), ATM (22%), and PIK3CA (17%) were the most frequently mutated genes. With respect to specific tumor subtypes, ESS showed mutations in the PDE4DIP, IGTA10, and DST genes, UCS exhibited mutations in ERBB4, and ULMS showed exclusive alterations in NOTCH2 and HER2. Mutations in the KMT2A gene were observed exclusively in ULM and ULMS. In silico pathway analyses demonstrated that many genes mutated in ULMS and ESS have functions associated with the cellular response to hypoxia and cellular response to peptide hormone stimulus. In UCS and ADS, genes with most alterations have functions associated with phosphatidylinositol kinase activity and glycerophospholipid metabolic process. CONCLUSION: This preliminary study observed pathogenic mutations in US and UCS samples. Further studies with a larger cohort and functional analyses will foster the development of a precision medicine-based approach for the treatment of US and UCS.


Subject(s)
Humans , Female , Sarcoma/genetics , Uterine Neoplasms/genetics , Carcinosarcoma/genetics , Brazil , Mutation
16.
J. venom. anim. toxins incl. trop. dis ; 27: e20200182, 2021. tab, graf, ilus
Article in English | ID: biblio-1250254

ABSTRACT

The accessory ß1 subunits, regulating the pharmacological and biophysical properties of BK channels, always undergo post-translational modifications, especially glycosylation. To date, it remains elusive whether the glycosylation contributes to the regulation of BK channels by ß1 subunits. Methods: Herein, we combined the electrophysiological approach with molecular mutations and biochemical manipulation to investigate the function roles of N-glycosylation in ß1 subunits. Results: The results show that deglycosylation of ß1 subunits through double-site mutations (ß1 N80A/N142A or ß1 N80Q/N142Q) could significantly increase the inhibitory potency of iberiotoxin, a specific BK channel blocker. The deglycosylated channels also have a different sensitivity to martentoxin, another BK channel modulator with some remarkable effects as reported before. On the contrary to enhancing effects of martentoxin on glycosylated BK channels under the presence of cytoplasmic Ca2+, deglycosylated channels were not affected by the toxin. However, the deglycosylated channels were surprisingly inhibited by martentoxin under the absence of cytoplasmic Ca2+, while the glycosylated channels were not inhibited under this same condition. In addition, wild type BK (α+ß1) channels treated with PNGase F also showed the same trend of pharmacological results to the mutants. Similar to this modulation of glycosylation on BK channel pharmacology, the deglycosylated forms of the channels were activated at a faster speed than the glycosylated ones. However, the V1/2 and slope were not changed by the glycosylation. Conclusion: The present study reveals that glycosylation is an indispensable determinant of the modulation of ß1-subunit on BK channel pharmacology and its activation. The loss of glycosylation of ß1 subunits could lead to the dysfunction of BK channel, resulting in a pathological state.(AU)


Subject(s)
Glycosylation , Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase , Mutation , Pharmacology
17.
Article in Chinese | WPRIM | ID: wpr-879626

ABSTRACT

OBJECTIVE@#To explore the genetic basis for a child suspected for Say-Barber-Biesecker-Young-Simpson syndrome.@*METHODS@#Genomic DNA was extracted from peripheral blood samples of the child and her parents. Whole exome sequencing was carried out for the proband. Suspected variants were validated by Sanger sequencing. The impact of the variants was predicted by bioinformatic analysis.@*RESULTS@#The child was found to harbor a de novo missense variant c.2623C>T (p.Asp875Tyr) in exon 13 of the KAT6B gene. The variant was previously unreported, and was not recorded in the major allele frequency database and predicted to be pathogenic based on PolyPhen-2, MutationTaster and PROVEAN analysis. As predicted by UCSF chimera and CASTp software, the variant can severely impact the substrate-binding pocket of histone acetyltransferase, resulting in loss of its enzymatic activity. Based on standards and guidelines by the American College of Medical Genetics and Genomics, the variant was classified to be likely pathogenic (PS2+PM2+PP3).@*CONCLUSION@#The child's condition may be attributed to the de novo missense c.2623C>T (p.Asp875Tyr) variant of the KAT6B gene.


Subject(s)
Blepharophimosis , Child , Congenital Hypothyroidism , Facies , Female , Heart Defects, Congenital , Histone Acetyltransferases/genetics , Humans , Intellectual Disability , Joint Instability , Mutation , Phenotype
18.
Article in Chinese | WPRIM | ID: wpr-879624

ABSTRACT

OBJECTIVE@#To explore the genetic basis for a patient with tuberous sclerosis complex.@*METHODS@#Genomic DNA was extracted from peripheral blood samples from members of his family and 100 unrelated healthy controls. The proband was subjected to next-generation sequencing, and candidate variant was confirmed by multiple ligation-dependent probe amplification (MLPA) and Sanger sequencing. Reverse transcription-PCR (RT-PCR) was carried out to determine the relative mRNA expression in the proband.@*RESULTS@#The patient was found to harbor a c.2355+1G>C splicing variant of the TSC2 gene. Sequencing of cDNA confirmed that 62 bases have been inserted into the 3' end of exon 21, which has caused a frameshift producing a truncated protein.@*CONCLUSION@#The novel splicing variant c.2355+1G>C of the TSC2 gene probably underlay the TSC in the proband. Above finding has expanded the variant spectrum of TSC2 and provided a basis for preimplantation genetic testing and/or prenatal diagnosis.


Subject(s)
Female , Humans , Mutation , Pregnancy , RNA Splicing/genetics , Tuberous Sclerosis/genetics , Tuberous Sclerosis Complex 1 Protein/genetics , Tuberous Sclerosis Complex 2 Protein/genetics
19.
Article in Chinese | WPRIM | ID: wpr-879608

ABSTRACT

OBJECTIVE@#To explore the genetic basis for a girl featuring bone and tooth mineralization disorder, premature deciduous teeth, rickets and short stature.@*METHODS@#Genomic DNA was extracted and subjected to high-throughput whole exome sequencing. Suspected variants were confirmed by Sanger sequencing. Impact of potential variants was analyzed with bioinformatic software.@*RESULTS@#The child was found to carry compound heterozygous missense variants of the ALPL gene, including c.1130C>T (p.A377V), a known pathogenic mutation inherited from her father, and c.1300G>A (p.V434M) inherited from her mother, which was unreported previously and predicted to be likely pathogenic based on standards and guidelines from the American College of Medical Genetics and Genomics (PM2+PM5+PP3+PP4).@*CONCLUSION@#The compound heterozygous variants of c.1130C>T (p.Ala377Val) and c.1300G>A (p.Val434Met) of the ALPL gene probably underlay the disease in this child. Above finding has enriched the spectrum of ALPL gene variants.


Subject(s)
Alkaline Phosphatase , Child , Female , Genomics , High-Throughput Nucleotide Sequencing , Humans , Hypophosphatasia/genetics , Mutation , Whole Exome Sequencing
20.
Article in Chinese | WPRIM | ID: wpr-879606

ABSTRACT

OBJECTIVE@#To explore the genetic variation of a Chinese family affected with congenital insensitivity to pain with anhidrosis and albinism.@*METHODS@#Whole exome sequencing (WES) was carried out to screen potential variants within genomic DNA extracted from the proband and his parents. Whole genome sequencing (WGS) was applied when variants were not found completely. Suspected variants were validated by Sanger sequencing.@*RESULTS@#WES has identified a heterozygous c.1729G>C (p.G577R) variant of NTRK1 gene and two heterozygous variants of OCA2 gene, namely c.1363A>G (p.R455G) and c.1182+1G>A. WGS has identified two additional heterozygous variants c.(851-798C>T; 851-794C>G) in deep intronic regions of the NTRK1 gene.@*CONCLUSION@#The compound heterozygous variants of the NTRK1 gene probably underlay the congenital insensitivity to pain with anhidrosis. And the compound heterozygous variants of the OCA2 gene probably underlay the albinism in the proband. In the case where no variant is detected by WES in the coding region, WGS should be considered to screen potential variants in the whole genome.


Subject(s)
Albinism , Child , DNA Mutational Analysis , Hereditary Sensory and Autonomic Neuropathies/genetics , Heterozygote , Humans , Membrane Transport Proteins , Mutation , Pedigree
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