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1.
Gene ; 715: 144027, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31374327

RESUMO

OBJECTIVES: To explore the clinical and molecular characteristics of a Chinese Zhuang minority patient with leukocyte adhesion deficiency type-1 (LAD-1) and glucose-6-phosphate dehydrogenase deficiency (G6PDD). METHODS: Routine clinical and physical examinations were performed, and patient data was collected and analyzed. Protein expression levels of Itgb2 and glucose-6-phosphate dehydrogenase (G6pd) proteins were assessed by flow cytometry and the glucose-6-phosphate (G6P) substrate method, respectively. Whole exome sequencing was performed to investigate genetic variations of the patient and his parents. RESULTS: The patient had fester disease and delayed separation of the umbilical cord at birth. Staphylococcus was detected in the fluid secretion of the auditory meatus of the patient. He exhibited a recurrent cheek scab, swollen hand, and swollen gum. Hematological examination indicated dramatic elevation of leukocytes including lymphocytes, monocytes, neutrophils and eosinophils. A novel homozygous mutation was detected in the ITGB2 gene of the patient, which was determined to be a two nucleotide deletion at the site of c.1537-1538 (c.1537-1538delGT), causing a frameshift of 24 amino acids from p.513 and inducing a stop codon (p.V513Lfs*24). A base substitution mutation was identified at c.1466 (c.1466G>T) of G6PD on chromosome X of the patient, which resulted in an amino acid change from arginine to leucine at p.489 (p.R489L). The patient also showed deficient lymphocyte expression of CD18 (2.99%) and significant downregulation of the G6pd protein. CONCLUSIONS: The patient was diagnosed with G6PDD and moderate LAD-1. The combination of LAD-1 and G6PDD in this case may have been due to the high incidence of genetic disease in this minority ethnic population. Analyzing existing LAD-1 and G6PDD cases from different populations can facilitate disease diagnosis and treatment. Particularly, reporting pathogenic mutations of LAD-1 and G6PDD will be crucial for genetic testing and prenatal diagnosis in an effort to decrease the incidence of these diseases.


Assuntos
Antígenos CD18/genética , Deficiência de Glucosefosfato Desidrogenase/genética , Homozigoto , Síndrome da Aderência Leucocítica Deficitária/genética , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Grupo com Ancestrais do Continente Asiático , Antígenos CD18/metabolismo , Deficiência de Glucosefosfato Desidrogenase/patologia , Humanos , Lactente , Síndrome da Aderência Leucocítica Deficitária/metabolismo , Síndrome da Aderência Leucocítica Deficitária/patologia , Leucócitos/metabolismo , Leucócitos/patologia , Masculino
2.
3.
Gene ; 718: 144072, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446095

RESUMO

Disorders of sex development (DSDs) are congenital conditions in which chromosomal, gonadal and sex is atypical. It is difficult to diagnose and manage patients with DSD in clinical practice, and the molecular etiology of DSD is still not completely understood. Here, we identified two novel pathogenic mutations from three unrelated Chinese patients with 46,XY complete gonadal dysgenesis (CGD) that is a clinical subgroup of DSD by whole exome sequencing. A novel mutation in the SRY gene (c.161delG) was identified in the first patient, and the second patient carried a novel missense mutation in the MAP3K1 gene (c.2117T>G). Bioinformatics analysis found that the deletion of SRY (c.161delG) led to a premature stop codon at amino acid 59 in the SRY protein, which resulted in lacking the DNA binding domain of SRY protein. Functional studies found that the missense mutation in the MAP3K1 gene (c.2117T>G) could interfere with the gene function through increasing the phosphorylation of the downstream targets of MAP3K1, ERK1/2 and p38, which resulted in reducing testis-determining factor SOX9 expression and increasing ovary-promoting factor ß-catenin activity. According to the American college of medical genetics and genomics (ACMG) standards and guidelines, these mutations were categorized as "pathogenic" mutations. Thus, our findings provide two novel pathogenic mutations associated with 46,XY CGD that can improve the etiological diagnosis for 46,XY CGD. ABBREVIATIONS.


Assuntos
Sequência de Bases , Disgenesia Gonadal 46 XY , MAP Quinase Quinase Quinase 1 , Mutação de Sentido Incorreto , Deleção de Sequência , Adulto , Grupo com Ancestrais do Continente Asiático , Feminino , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal 46 XY/patologia , Humanos , MAP Quinase Quinase Quinase 1/genética , MAP Quinase Quinase Quinase 1/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Masculino , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Proteína da Região Y Determinante do Sexo/genética , Proteína da Região Y Determinante do Sexo/metabolismo
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(8): 757-760, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31400121

RESUMO

OBJECTIVE: To identify pathogenic variations of EXT1 and EXT2 genes in two Chinese pedigrees affected with hereditary multiple exostosis (HME). METHODS: Genomic DNA was extracted from peripheral blood samples using a phenol-chloroform method. PCR and Sanger sequencing was conducted to amplify the exons and the flanking intronic regions of the EXT1 and EXT2 genes. RESULTS: DNA sequencing has revealed a heterozygous missense variation c.812A>G (p.Tyr271Cys) in the exon 1 of EXT1 in pedigree 1, and a heterozygous frameshift variation c.1431dup (p.Ser478Leufs*43) in the exon 6 of EXT1 in the proband from pedigree 2. Both variations have co-segregated with the disease phenotype, which was also consistent with previous report. CONCLUSION: Two heterozygous pathogenic variations underlying HME have been identified. The result has facilitated genetic counseling and prenatal diagnosis for the affected pedigrees.


Assuntos
Exostose Múltipla Hereditária/genética , N-Acetilglucosaminiltransferases/genética , Grupo com Ancestrais do Continente Asiático , Sequência de Bases , Análise Mutacional de DNA , Exostose Múltipla Hereditária/patologia , Mutação da Fase de Leitura , Humanos , Mutação de Sentido Incorreto , Linhagem
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(8): 794-797, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31400130

RESUMO

OBJECTIVE: To explore the molecular basis for a pedigree affected with Darier-White disease. METHODS: Genomic DNA was isolated from 3 patients and 1 unaffected member from the pedigree, as well as 80 healthy controls. Targeted sequence capture and next-generation sequencing were used to screen mutations of skin disease-related genes. Candidate mutations were verified by Sanger sequencing, and co-segregation analysis was carried out to confirm the pathogenicity of mutation. Conservation analysis and protein structure and function were also predicted with Bioinformatic tools. RESULTS: A heterozygous mutation c.2246G>T (p.G749V) was identified in exon 15 of ATP2A2 gene in all 3 patients from the pedigree, but not in the unaffected member or 80 healthy controls. The corresponding amino acid was highly conserved, and mutation of which can lead to structural and functional changes of the protein. CONCLUSION: The c.2246G>T missense mutation of the ATP2A2 gene probably underlies the Darier-White disease in this pedigree by causing damages to the structure and function of sarcoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2).


Assuntos
Doença de Darier/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Heterozigoto , Humanos , Mutação de Sentido Incorreto , Linhagem
6.
Gene ; 715: 143970, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31330235

RESUMO

BACKGROUND: Bicuspid aortic valve (BAV) formation is genetically determined, with reduced penetrance and variable expressivity. NOTCH1 is a proven candidate gene and its mutations have been found in familial and sporadic cases of BAV. METHODS: 66 BAV patients from the GISSI VAR study were genotyped for the NOTCH1 gene. RESULTS: We identified 63 variants, in heterozygous and homozygous states. Fifty-two are common polymorphisms present in almost all patients. Eleven variants are new and never yet reported: two are non-synonymous substitutions, Gly540Asp in exon 10 and Glu851Gln in exon 16; one is in the 3'UTR region and seven in introns, one corresponds to a T allele insertion in intron 27. We selected four statistically noteworthy and seven new variants identified in six BAV patients and correlated them with clinical and demographic variables and with imaging and histological parameters. Preliminary data show that four were BAV patients with isolated stenosis in patients over 60 aged. These variants may correlate with a later need for surgery for the presence of stenosis and not aortic valve regurgitation or ascending aortic aneurysm. CONCLUSIONS: Completing the genotyping of 62 BAV patients we found 11 new variants in the NOTCH1 gene never yet reported. These findings confirm that the identification of new, clinically remarkable biomarkers for BAV requires a deeper genetic understanding of the NOTCH1 gene variants, which could be targeted by future diagnostic and therapeutic strategies.


Assuntos
Estenose da Valva Aórtica/genética , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas , Mutação de Sentido Incorreto , Penetrância , Receptor Notch1/genética , Adulto , Alelos , Substituição de Aminoácidos , Éxons , Feminino , Heterozigoto , Homozigoto , Humanos , Íntrons , Itália , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sequência de DNA
7.
Gene ; 714: 143990, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31326550

RESUMO

BACKGROUND: Progressive cardiac conduction defect (PCCD), also known as Lenegre-Lev disease, is one of the most common heart conduction abnormalities. Previous studies have screened for known mutation sites that cause heart block in a 68-person family with a history of PCCD, revealed no mutations. OBJECTIVE: To screen pathogenic genes of the PCCD family and to study the function of the gene mutations related to heart block diseases. METHODS: Whole exome sequencing (WES) was performed on two PCCD patients and one non-PCCD family member to find the related pathogenic gene. After family co-segregation and preliminary functional analysis, we identified the mutant gene CLCA2. To study the function of this gene, we constructed mutant-gene mice using CRISPR-Cas9 technology, and electrocardiogram monitoring was performed after genotype verification. RESULTS: The CLCA2 c.G1725T mutation was identified and co-segregated with the phenotype. The analysis showed that the CLCA2 c.G1725T mutation is harmful and mainly affects protein glycosylation. Immunofluorescence staining revealed that CLCA2 was highly expressed in the sinoatrial node (SAN) tissues. Electrocardiogram monitoring of the mice revealed that CLCA2 point mutations induced mild conduction block and ectopic pacemakers. CONCLUSION: Our findings indicate that a novel heterozygous missense mutation c.G1725T of the CLCA2 gene may be associated with heart block disease and the mutation in this gene may lead to sinus node lesions and conduction blocking.


Assuntos
Canais de Cloreto/genética , Bloqueio Cardíaco/genética , Mutação de Sentido Incorreto/genética , Sequência de Aminoácidos , Animais , Eletrocardiografia/métodos , Feminino , Heterozigoto , Humanos , Masculino , Camundongos , Linhagem , Fenótipo , Mutação Puntual/genética , Nó Sinoatrial/patologia
8.
Vet Microbiol ; 235: 21-24, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282375

RESUMO

Occurrence of avian influenza (AI) with Neuraminidase (NA) mutations which confer reduced neuraminidase inhibitor (NAI) susceptibility has remained a cause of concern. The susceptibility to NAIs of 67 highly pathogenic avian influenza H5N1 viruses isolated during 2006-2012 in India was tested in phenotypic fluorescence-based NA inhibition assay, sequence analysis and in ovo. One isolate showed a novel NA I117T amino acid substitution (N2 numbering) and eight isolates showed previously known NAI-resistance marker mutations (I117V, E119D, N294S, total 9/67). The overall incidence of resistant variants was 13.4%. The novel I117T substitution reduced oseltamivir susceptibility by 18.6-fold and zanamivir susceptibility by 11.8-fold, compared to the wild type AI H5N1virus, thus showed cross-resistance to both oseltamivir and zanamivir in NA inhibition assays. However, the other two isolates with I117V substitution were sensitive to both the NAIs. In addition, the comparison of growth of the I117T and I117V variants in presence of NAI's in the in ovo assays exhibited difference in growth levels. The present study reports the natural occurrence of a novel I117T mutation in AI H5N1 virus conferring cross-resistance to oseltamivir and zanamivir highlighting the urgent need of antiviral surveillance of AI viruses.


Assuntos
Antivirais/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Neuraminidase/genética , Oseltamivir/farmacologia , Proteínas Virais/genética , Zanamivir/farmacologia , Substituição de Aminoácidos , Animais , Galinhas , Farmacorresistência Viral , Índia , Virus da Influenza A Subtipo H5N1/genética , Concentração Inibidora 50 , Mutação de Sentido Incorreto , Zigoto
9.
Nat Commun ; 10(1): 2493, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175300

RESUMO

Tauopathies are neurodegenerative diseases characterized by intracellular amyloid deposits of tau protein. Missense mutations in the tau gene (MAPT) correlate with aggregation propensity and cause dominantly inherited tauopathies, but their biophysical mechanism driving amyloid formation is poorly understood. Many disease-associated mutations localize within tau's repeat domain at inter-repeat interfaces proximal to amyloidogenic sequences, such as 306VQIVYK311. We use cross-linking mass spectrometry, recombinant protein and synthetic peptide systems, in silico modeling, and cell models to conclude that the aggregation-prone 306VQIVYK311 motif forms metastable compact structures with its upstream sequence that modulates aggregation propensity. We report that disease-associated mutations, isomerization of a critical proline, or alternative splicing are all sufficient to destabilize this local structure and trigger spontaneous aggregation. These findings provide a biophysical framework to explain the basis of early conformational changes that may underlie genetic and sporadic tau pathogenesis.


Assuntos
Agregação Patológica de Proteínas/genética , Tauopatias/genética , Proteínas tau/genética , Motivos de Aminoácidos/genética , Simulação por Computador , Células HEK293 , Humanos , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Mutação de Sentido Incorreto , Agregação Patológica de Proteínas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Proteínas tau/metabolismo , Proteínas tau/ultraestrutura
10.
BMC Med Genet ; 20(1): 101, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174490

RESUMO

BACKGROUND: N-terminal acetylation is a common protein modification in human cells and is catalysed by N-terminal acetyltransferases (NATs), mostly cotranslationally. The NAA10-NAA15 (NatA) protein complex is the major NAT, responsible for acetylating ~ 40% of human proteins. Recently, NAA10 germline variants were found in patients with the X-linked lethal Ogden syndrome, and in other familial or de novo cases with variable degrees of developmental delay, intellectual disability (ID) and cardiac anomalies. METHODS: Here we report a novel NAA10 (NM_003491.3) c.248G > A, p.(R83H) missense variant in NAA10 which was detected by whole exome sequencing in two unrelated boys with intellectual disability, developmental delay, ADHD like behaviour, very limited speech and cardiac abnormalities. We employ in vitro acetylation assays to functionally test the impact of this variant on NAA10 enzyme activity. RESULTS: Functional characterization of NAA10-R83H by in vitro acetylation assays revealed a reduced enzymatic activity of monomeric NAA10-R83H. This variant is modelled to have an altered charge density in the acetyl-coenzyme A (Ac-CoA) binding region of NAA10. CONCLUSIONS: We show that NAA10-R83H has a reduced monomeric catalytic activity, likely due to impaired enzyme-Ac-CoA binding. Our data support a model where reduced NAA10 and/or NatA activity cause the phenotypes observed in the two patients.


Assuntos
Acetiltransferases/genética , Deficiência Intelectual/genética , Microcefalia/genética , Mutação de Sentido Incorreto , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Acetilação , Acetiltransferases/metabolismo , Sequência de Aminoácidos , Pré-Escolar , Humanos , Lactente , Masculino , Modelos Moleculares , Acetiltransferase N-Terminal A/química , Acetiltransferase N-Terminal A/metabolismo , Acetiltransferase N-Terminal E/química , Acetiltransferase N-Terminal E/metabolismo , Fenótipo , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Sequenciamento Completo do Exoma
11.
Nat Commun ; 10(1): 2569, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189880

RESUMO

Synonymous mutations have been viewed as silent mutations, since they only affect the DNA and mRNA, but not the amino acid sequence of the resulting protein. Nonetheless, recent studies suggest their significant impact on splicing, RNA stability, RNA folding, translation or co-translational protein folding. Hence, we compile 659194 synonymous mutations found in human cancer and characterize their properties. We provide the user-friendly, comprehensive resource for synonymous mutations in cancer, SynMICdb ( http://SynMICdb.dkfz.de ), which also contains orthogonal information about gene annotation, recurrence, mutation loads, cancer association, conservation, alternative events, impact on mRNA structure and a SynMICdb score. Notably, synonymous and missense mutations are depleted at the 5'-end of the coding sequence as well as at the ends of internal exons independent of mutational signatures. For patient-derived synonymous mutations in the oncogene KRAS, we indicate that single point mutations can have a relevant impact on expression as well as on mRNA secondary structure.


Assuntos
Bases de Dados de Ácidos Nucleicos , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias/genética , Mutação Silenciosa/genética , Conjuntos de Dados como Assunto , Humanos , Mutação de Sentido Incorreto/genética , Mutação Puntual/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Dobramento de RNA/genética , Processamento de RNA/genética , RNA Mensageiro/química , RNA Mensageiro/genética
12.
Nat Commun ; 10(1): 2562, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189898

RESUMO

Cadmium (Cd) accumulation in rice grain poses a serious threat to human health. While several transport systems have been reported, the complicity of rice Cd transport and accumulation indicates the necessity of identifying additional genes, especially those that are responsible for Cd accumulation divergence between indica and japonica rice subspecies. Here, we show that a gene, OsCd1, belonging to the major facilitator superfamily is involved in root Cd uptake and contributes to grain accumulation in rice. Natural variation in OsCd1 with a missense mutation Val449Asp is responsible for the divergence of rice grain Cd accumulation between indica and japonica. Near-isogenic line tests confirm that the indica variety carrying the japonica allele OsCd1V449 can reduce the grain Cd accumulation. Thus, the japonica allele OsCd1V449 may be useful for reducing grain Cd accumulation of indica rice cultivars through breeding.


Assuntos
Cádmio/metabolismo , Grão Comestível/metabolismo , Proteínas de Membrana/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Alelos , Asparagina/genética , Cádmio/análise , Membrana Celular/metabolismo , Grão Comestível/química , Humanos , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Oryza/química , Oryza/genética , Filogenia , Melhoramento Vegetal/métodos , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Poluentes do Solo/análise , Valina/genética
13.
Hum Genet ; 138(7): 771-785, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31168774

RESUMO

Modulation of dystrophin pre-mRNA splicing is an attractive strategy to ameliorate the severe phenotype of Duchenne muscular dystrophy (DMD), although this requires a better understanding of the mechanism of splicing regulation. Aberrant splicing caused by gene mutations provides a good model to study splicing regulatory cis-elements and binding proteins. In this study, we identified skipping of in-frame exon 25 induced by a nonsense mutation (NM_004006.2:c.3340A > T;p.Lys1114*) in the DMD gene. Site-directed mutagenesis study in minigenes suggested that c.3340A > T converts an exonic splicing enhancer sequence (ESE) to a silencer element (ESS). Indeed, RNA pull-down and functional study provided evidence that c.3340A > T abolishes the binding of the splicing enhancer protein Tra2ß and promotes interactions with the repressor proteins hnRNP A1, hnRNP A2, and hnRNP H. By carefully analyzing the sequence motif encompassing the mutation site, we concluded that the skipping of exon 25 was due to disruption of a Tra2ß-dependent ESE and the creation of a new ESS associated with hnRNP A1 and hnRNP A2, which in turn increased the recruitment of hnRNP H to a nearby binding site. Finally, we demonstrated that c.3340A > T impairs the splicing of upstream intron 24 in a splicing minigene assay. In addition, we showed that the correct splicing of exon 25 is finely regulated by multiple splicing regulators that function in opposite directions by binding to closely located ESE and ESS. Our results clarify the detailed molecular mechanism of exon skipping induced by the nonsense mutation c.3340A > T and also provide information on exon 25 splicing.


Assuntos
Distrofina/genética , Elementos Facilitadores Genéticos , Éxons , Distrofia Muscular de Duchenne/genética , Mutação de Sentido Incorreto , Processamento de RNA , Elementos Silenciadores Transcricionais , Adolescente , Regulação da Expressão Gênica , Humanos , Masculino , Distrofia Muscular de Duchenne/patologia
14.
BMC Bioinformatics ; 20(1): 363, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253089

RESUMO

BACKGROUND: Missense mutations in the first five exons of F9, which encodes factor FIX, represent 40% of all mutations that cause hemophilia B. To address the ongoing debate regarding in silico identification of disease-causing mutations at these exons, we analyzed 215 missense mutations from www.factorix.org using six in silico prediction tools, which are the most common used programs for analysis prediction of impact of mutations on the protein structure and function, with further advantage of using similar approaches. We developed different algorithms to integrate multiple predictions from such tools. In order to approach a structural analysis on FIX we performed a modeling of five selected pathogenic mutations. RESULTS: SIFT, PolyPhen-2 HumDiv, SNAP2, and MutationAssessor were the most successful in identifying true non-causative and causative mutations. A proposed function integrating these algorithms (wgP4) was the most sensitive (90.1%), specific (22.6%), and accurate (87%) than similar functions, and identified 187 variants as deleterious. Clinical phenotype was significantly associated with predicted causative mutations at all five exons. However, PolyPhen-2 HumDiv was more successful in linking clinical severity to specific exons, while functions that integrate 4-6 predictions were more successful in linking phenotype to genotypes at the light chain (exons 3-5). The most important value of integrating multiple predictions is the inclusion of scores derived from different approaches. Modeling of protein structure showed the effects of pathogenic nsSNPs on structure and function of FIX. CONCLUSIONS: A simple function that integrates information from different in silico programs yields the best prediction of mutated phenotypes. However, the specificity, sensitivity, and accuracy of genotype-phenotype predictions depend on specific characteristics of the protein domain and the disease of interest as we validated by the structural analysis of selected pathogenic F9 mutations. The proposed function integrating algorithm (wgP4) might be useful for the analysis of nsSNPs impact on other genes.


Assuntos
Biologia Computacional/métodos , Simulação por Computador , Éxons/genética , Fator IX/genética , Hemofilia B/genética , Mutação de Sentido Incorreto , Algoritmos , Genótipo , Humanos , Fenótipo
16.
Comput Biol Chem ; 80: 472-479, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31174159

RESUMO

To understand the structural and functional importance of PIK3CA somatic mutations, whole exome sequencing, molecular dynamics simulation techniques in combination with in silico prediction algorithms such as SIFT, PolyPhen, Provean and CADD were employed. Twenty out of eighty missense somatic mutations in PIK3CA gene were found to be pathogenic by all the four algorithms. Most recurrent mutations found were known hotspot PIK3CA mutations with known clinical significance like p.E545 K, p.E545A, p.E545 G and p.C420R. A missense mutation p.G118D was found to be recurrently mutated in 5 cases. Interestingly, this mutation was observed in one of the patients who underwent whole exome sequencing and was completely absent from the controls. To see the effect of this mutation on the structure of PIK3CA protein, molecular dynamics simulation was performed. By molecular dynamics approach, we have shown that p.G118D mutation deviated from the native structure which was supported by the decrease in the number of hydrogen bonds, difference in hydrogen bond distance and angle, difference in root mean square deviation between the native and the mutant structures.


Assuntos
Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Algoritmos , Biologia Computacional/métodos , Feminino , Humanos , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto , Sequenciamento Completo do Exoma
17.
BMC Med Genet ; 20(1): 95, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31151415

RESUMO

BACKGROUND: Tubulinopathies result from mutations in tubulin genes, including TUBG1, responsible for cell microtubules, are characterized by brain development abnormalities, microcephaly, early-onset epilepsy, and motor impairment. Only eleven patients with TUBG1 mutations have been previously described in literature to our knowledge. Here we present two new patients with novel de novo TUBG1 mutations and review other cases in the literature. CASE PRESENTATIONS: Both patients have microcephaly and intellectual disability. Patient B further fits a more typical presentation, with well-controlled epilepsy and mild hypertonia, whereas Patient A's presentation is much milder without these other features. CONCLUSION: This report expands the spectrum of TUBG1 mutation manifestations, suggesting the possibility of less severe phenotypes for patients and families, and influencing genetic counselling strategies.


Assuntos
Predisposição Genética para Doença/genética , Mutação de Sentido Incorreto , Transtornos do Neurodesenvolvimento/genética , Tubulina (Proteína)/genética , Criança , Feminino , Humanos , Lactente , Masculino , Transtornos do Neurodesenvolvimento/patologia , Fenótipo , Índice de Gravidade de Doença
18.
Nat Commun ; 10(1): 2201, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101814

RESUMO

Systemic lupus erythematosus (SLE) is the prototypic systemic autoimmune disease. It is thought that many common variant gene loci of weak effect act additively to predispose to common autoimmune diseases, while the contribution of rare variants remains unclear. Here we describe that rare coding variants in lupus-risk genes are present in most SLE patients and healthy controls. We demonstrate the functional consequences of rare and low frequency missense variants in the interacting proteins BLK and BANK1, which are present alone, or in combination, in a substantial proportion of lupus patients. The rare variants found in patients, but not those found exclusively in controls, impair suppression of IRF5 and type-I IFN in human B cell lines and increase pathogenic lymphocytes in lupus-prone mice. Thus, rare gene variants are common in SLE and likely contribute to genetic risk.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Proteínas de Membrana/genética , Quinases da Família src/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adolescente , Adulto , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Estudos de Casos e Controles , Linhagem Celular , Núcleo Celular/imunologia , Núcleo Celular/metabolismo , Criança , Modelos Animais de Doenças , Feminino , Frequência do Gene , Células HEK293 , Voluntários Saudáveis , Humanos , Fatores Reguladores de Interferon/imunologia , Fatores Reguladores de Interferon/metabolismo , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação de Sentido Incorreto , Sequenciamento Completo do Exoma , Quinases da Família src/metabolismo
19.
Nat Commun ; 10(1): 2213, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101826

RESUMO

Spiradenoma and cylindroma are distinctive skin adnexal tumors with sweat gland differentiation and potential for malignant transformation and aggressive behaviour. We present the genomic analysis of 75 samples from 57 representative patients including 15 cylindromas, 17 spiradenomas, 2 cylindroma-spiradenoma hybrid tumors, and 24 low- and high-grade spiradenocarcinoma cases, together with morphologically benign precursor regions of these cancers. We reveal somatic or germline alterations of the CYLD gene in 15/15 cylindromas and 5/17 spiradenomas, yet only 2/24 spiradenocarcinomas. Notably, we find a recurrent missense mutation in the kinase domain of the ALPK1 gene in spiradenomas and spiradenocarcinomas, which is mutually exclusive from mutation of CYLD and can activate the NF-κB pathway in reporter assays. In addition, we show that high-grade spiradenocarcinomas carry loss-of-function TP53 mutations, while cylindromas may have disruptive mutations in DNMT3A. Thus, we reveal the genomic landscape of adnexal tumors and therapeutic targets.


Assuntos
Carcinoma Adenoide Cístico/genética , Enzima Desubiquitinante CYLD/genética , Proteínas Quinases/genética , Neoplasias das Glândulas Sudoríparas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoide Cístico/patologia , Estudos de Coortes , DNA (Citosina-5-)-Metiltransferases/genética , Análise Mutacional de DNA , Feminino , Humanos , Mutação com Perda de Função , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Domínios Proteicos/genética , Neoplasias das Glândulas Sudoríparas/patologia , Glândulas Sudoríparas/patologia , Proteína Supressora de Tumor p53/genética , Sequenciamento Completo do Exoma
20.
Medicine (Baltimore) ; 98(20): e15617, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31096470

RESUMO

RATIONALE: Currently, the relationship between heterozygous mutations in SLC34A1 and hypophosphatemia is controversial. Here we report an autosomal dominant hypophosphatemia pedigree carrying a novel heterozygous mutation in SLC34A1. PATIENT CONCERNS: The proband is a 32-year old young man, presented with progressive pain and weakness in his lower extremities for more than 5 years. The proband showed persistent hypophosphatemia and low TmPO4/GFR values, indicating renal phosphate leak. His grandfather, father, and one of his uncles showed the similar symptoms. DIAGNOSES: Autosomal dominant hypophosphatemia. INTERVENTIONS AND OUTCOMES: Phosphorus supplement was prescribed to the proband and his affected uncle. Both their serum phosphorus levels recovered to normal and their symptoms such as back pain and lower extremity weakness were completely relieved. Whole exome sequencing was performed to identify disease-causing mutations in proband. LESSONS: A novel heterozygous missense mutation c.680A>G (p. N227S) in exon 7 of SLC34A1 was found in proband by whole exome sequencing, which was also found in other 4 family members of this pedigree. Our report of an autosomal dominant hypophosphatemia pedigree with 5 mutant carriers enriches the clinical phenotype caused by the SLC34A1 mutations and further affirms the heterozygous mutations are causative for hypophosphatemia.


Assuntos
Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Raquitismo Hipofosfatêmico Familiar/genética , Fósforo/uso terapêutico , Raquitismo/tratamento farmacológico , Raquitismo/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/genética , Adulto , Raquitismo Hipofosfatêmico Familiar/diagnóstico , Humanos , Masculino , Mutação de Sentido Incorreto , Raquitismo/diagnóstico
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