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Objective:To investigate the clinical phenotype and genetic characteristics of developmental epileptic encephalopathy 18 (DEE18) caused by SZT2 gene variants. Methods:Clinical data of 2 children with SZT2 related DEE18 who visited the Department of Pediatric Neurology, Linyi People′s Hospital in March 2020 and July 2023 were collected. The whole exome sequencing (WES) and Sanger sequencing were applied to verify the child and their parents. SWISS-MODEL software was used to perform protein 3D modeling for the selected SZT2 gene variants. Results:Both of the 2 cases showed severe global developmental delay, epileptic seizures, autism, megacephaly, facial deformity, hypotonia, corpus callosum malformation, persistent cavum septum pellucidum, and slow background activity and focal discharge in video electroencephalography. Case 1 was easy to startle and thin in stature; case 2 had immune deficiency and clustered seizures. WES results showed that case 1 carried a compound heterozygous variant of c.5811G>A (p.W1937X) (paternal) and c.9269delG (p.S3090Ifs *94) (maternal), while case 2 carried a compound heterozygous variant of c.6302A>C(p.H2101P) (paternal) and c.7584dupA (p.E2529Rfs *20) (maternal), the parents of both patients with normal clinical phenotypes. The 4 mutations mentioned above were novel variations that had not yet been reported domestically or internationally. According to the American College of Medical Genetics and Genomics variant classification criteria and guidelines, the p.S3090Ifs *94 variant was interpreted as pathogenic; p.W1937X variant was interpreted as pathogenic; p.E2529Rfs *20 variant was interpreted as likely pathogenic; p.H2101P variant was interpreted as uncertain significance. 3D modeling showed that the variant of p.H2101P resulted in a significant change in the hydrogen bond around the 2 101st amino acid encoded, leading to a decrease in protein stability. The other 3 variants led to early truncation of peptide chain and obvious changes in protein structure. Conclusions:DEE18 caused by SZT2 gene mutation is mainly an autosome recessive genetic disease, and its clinical manifestations include global developmental delay, epileptic seizures, autism, craniofacial malformation, hypotonia, epileptic discharge, corpus callosum malformation, persistent cavum septum pellucidum, shock, small and thin stature, and immune deficiency. Four novel variants related to the SZT2 gene may be the genetic etiology of DEE18 patients in this study.
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A 2-year-old boy was admitted to Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine in Nov 30th, 2018, due to polydipsia, polyphagia, polyuria accompanied with increased glucose levels for more than 2 weeks. He presented with symmetrical short stature [height 81 cm (-2.2 SD), weight 9.8 kg (-2.1 SD), body mass index 14.94 kg/m2 (P10-P15)], and with no special facial or physical features. Laboratory results showed that the glycated hemoglobin A1c was 14%, the fasting C-peptide was 0.3 ng/mL, and the islet autoantibodies were all negative. Oral glucose tolerance test showed significant increases in both fasting and postprandial glucose, but partial islet functions remained (post-load C-peptide increased 1.43 times compared to baseline). A heterozygous variant c.1366C>T (p.R456C) was detected in GATA6 gene, thereby the boy was diagnosed with a specific type of diabetes mellitus. The boy had congenital heart disease and suffered from transient hyperosmolar hyperglycemia after a patent ductus arteriosus surgery at 11 months of age. Insulin replacement therapy was prescribed, but without regular follow-up thereafter. The latest follow-up was about 3.5 years after the diagnosis of diabetes when the child was 5 years and 11 months old, with the fasting blood glucose of 6.0-10.0 mmol/L, and the 2 h postprandial glucose of 17.0-20.0 mmol/L.
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Masculino , Criança , Humanos , Pré-Escolar , Lactente , Diabetes Mellitus Tipo 2/complicações , Mutação de Sentido Incorreto , Peptídeo C/genética , China , Insulina/genética , Glucose , Glicemia , Fator de Transcrição GATA6/genéticaRESUMO
This study aimed to identify subtypes of genomic variants associated with the efficacy of immune checkpoint inhibitors (ICIs) by conducting systematic literature search in electronic databases up to May 31, 2021. The main outcomes including overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and durable clinical benefit (DCB) were correlated with tumor genomic features. A total of 1546 lung cancer patients with available genomic variation data were included from 14 studies. The Kirsten rat sarcoma viral oncogene homolog G12C (KRASG12C) mutation combined with tumor protein P53 (TP53) mutation revealed the promising efficacy of ICI therapy in these patients. Furthermore, patients with epidermal growth factor receptor (EGFR) classical activating mutations (including EGFRL858R and EGFRΔ19) exhibited worse outcomes to ICIs in OS (adjusted hazard ratio (HR), 1.40; 95% confidence interval (CI), 1.01‒1.95; P=0.0411) and PFS (adjusted HR, 1.98; 95% CI, 1.49‒2.63; P<0.0001), while classical activating mutations with EGFRT790M showed no difference compared to classical activating mutations without EGFRT790M in OS (adjusted HR, 0.96; 95% CI, 0.48‒1.94; P=0.9157) or PFS (adjusted HR, 0.72; 95% CI, 0.39‒1.35; P=0.3050). Of note, for patients harboring the Usher syndrome type-2A(USH2A) missense mutation, correspondingly better outcomes were observed in OS (adjusted HR, 0.52; 95% CI, 0.32‒0.82; P=0.0077), PFS (adjusted HR, 0.51; 95% CI, 0.38‒0.69; P<0.0001), DCB (adjusted odds ratio (OR), 4.74; 95% CI, 2.75‒8.17; P<0.0001), and ORR (adjusted OR, 3.45; 95% CI, 1.88‒6.33; P<0.0001). Our findings indicated that, USH2A missense mutations and the KRASG12Cmutation combined with TP53 mutation were associated with better efficacy and survival outcomes, but EGFR classical mutations irrespective of combination with EGFRT790M showed the opposite role in the ICI therapy among lung cancer patients. Our findings might guide the selection of precise targets for effective immunotherapy in the clinic.
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Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Proteínas da Matriz Extracelular/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/genética , Resultado do TratamentoRESUMO
Objective:To analyze the clinical phenotype and gene sequencing results of a child with hyperekplexia, and to clarify her genetic etiology.Methods:The clinical information of the child was collected, and the whole exome sequencing of the child and her parents was performed. The suspected pathogenic variants were verified by Sanger sequencing and bioinformatics analysis.Results:There was a 12 years old girl, who was hospitalized in the Department of Pediatric Neurology of Linyi People′s Hospital because of "paroxysmal limb stiffness for more than 11 years and aggravated for half a month" on July 4, 2022. The girl showed exaggerated startle reflexes and generalized siffness in response to external sudden, unexpected stimuli, occasionally accompanied by apnea and cyanosis, frequent attacks occurred several times a day, lasting for 1-30 minutes, and early head and abdomen flexion can be relieved. She showed normal growth and development, no abnormality in brain magnetic resonance imaging and video electroencephalogram during seizure. The whole exome sequencing showed that there was a missense heterozygous mutation c.643T>C(p.W215R) in the SLC6A5 gene of the child. Neither of the parents carried this mutation, which was a novel and de novo variant. According to the guidelines of American College of Medical Genetics and Genomics, this variant was a likely pathogenic variant [PS2: de novo (both maternity and paternity confirmed) in the patient with the disease and no family history; PM2: undetected variants in the normal population; PP3: multiple softwares predicted that this mutation would have harmful effects on genes or gene products], and highly conserved. Swiss modeling found that the hydrogen bond of the modified amino acid also changed. Conclusions:Hyperekplexia is relatively rare and prone to misdiagnosis. The main clinical features are excessive startle reflexes (limb shaking, or jumping) to unexpected external stimuli, resulting in overall stiffness, normal growth and development, and normal video electroencephalogram during the seizure. The likely pathogenic heterozygous missense variant c.643T>C (p.W215R) of SLC6A5 gene is the genetic cause of this case.
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Objective@# To explore the pathogenic genes in a Chinese family affected by nonsyndromic tooth agenesis so as to study the pathogenesis of oligodontia.@*Methods @# Hospital ethical approval and informed consent of the patients and family members were obtained. Clinical data of the proband and close family members were collected, peripheral venous blood was collected, and DNA was extracted. Gene sequencing was performed through whole-exome sequencing, and then the screened pathogenic genes were verified by Sanger sequencing. The three-dimensional structure of the mutant proteins was analyzed and compared with the wild-type using bioinformatics tools.@*Results@#The two patients with congenital majority tooth loss in this family were cousins, and there were no other patients with congenital majority tooth loss in the family. Besides congenital multiple tooth loss, the two patients had no obvious hair abnormalities, finger/toe abnormalities, sweating abnormalities or other abnormal manifestations of ectodermal tissue. We found a mutant gene that in this family by carrying out gene sequencing of the patients and their close family members. A novel EDA (ectodysplasin A) missense mutation c.983C>T (p. Pro328Leu) was identified, which changed the encoded amino acid from proline (Pro) to leucine (Leu). Analysis of the mutation site showed that the site was highly conserved, and three-dimensional structure modeling also found that it changed the structure of EDA. @* Conclusion@#A novel EDA missense variant (c.983C>T, p.Pro328Leu) was first identified in a Chinese family with nonsyndromic tooth agenesis, extending the mutation spectrum of the EDA gene.
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ABSTRACT Background: Fukuyama congenital muscular dystrophy (FCMD) is the most common form of a group of autosomal recessive disorders characterized by altered α-dystroglycan glycosylation and caused by FKTN gene mutations. However, mutations of this gene may cause a broad range of phenotypes, including Walker-Warburg syndrome, muscle-brain-eye disease, FCMD, limb-girdle muscular dystrophy without mental retardation, and cardiomyopathy with no or minimal skeletal muscle weakness. Objective: Our purpose was to describe two siblings who died at a young age with dilated cardiomyopathy (DCM), no muscle weakness, or atrophy, and were homozygous for a FKTN missense mutation. Methods: Site-directed next-generation sequencing (NGS) was performed. Pathogenicity of variants of interest was established according to the American College of Medical Genetics (ACMG) criteria, and all available first-degree relatives were screened for mutations by Sanger sequencing. Results: NGS revealed a homozygous FKTN variant in the index case (p.Gly424Ser, rs752358445), classified as likely pathogenic by ACMG criteria. Both parents and an unaffected brother were heterozygous carriers. Since the siblings had no apparent skeletal muscle weakness or central nervous system involvement, FKTN mutations were not initially suspected. Conclusions: This is the first report demonstrating that heterozygous individuals for the FKTN p.Gly424Ser mutation were healthy, while two homozygous brothers suffered severe DCM, strongly suggesting that this FKTN mutation is a rare cause of autosomal recessive DCM.
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Objective:To explore the genetic etiology for a premature ovarian insufficiency (POI) patient from a consanguineous Chinese family, and to provide basis for genetic counseling and fertility counseling.Methods:Whole-exome sequencing was performed using DNA extracted from the blood sample of POI patient. Suspected pathogenic mutation was analyzed by bioinformatics methods and verified by Sanger sequencing. The pathogenicity of the variation was assessed according to the ACMG genetic variation classification criteria and guidelines.Results:A homozygous variation, c. 32G>T (p.G11V), of PSMC3IP was identified in the patient. Bioinformatics analysis revealed that the variation was conserved in different animal species, and this variation was classified as possible pathogenic variation according to the ACMG genetic variation classification criteria and guidelines.Conclusions:The homozygous missense variation of PSMC3IP is the cause of the POI patient in this family. We are reporting for the first time the missense variation in PSMC3IP gene caused POI, which enriched the mutation spectrum of PSMC3IP and provided the basis for genetic counseling and fertility guidance of this family.
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Objective:To analyze the clinical features and SCN4A gentic background of a family with hypokalemic periodic paralysis.Methods:Peripheral blood samples and clinical data were collected from the proband, his brother and parents, and genomic DNA was extracted from these blood samples. Genome-wide exome sequencing was conducted to determine the mutation site in the proband and then allele-specific oligonucleotide primers were designed based on the mutation site. Polymerase chain reaction (PCR) was performed to detect the mutation site to further identify the causative gene in the family.Results:The patient was a 19-years-old male, Han nationality. The patient presented with periodic paralysis while hypokalemia at the same time. His father and grandpa have a similar medical history in the family. A hybrid missense variation (p.R672H) was identified in exon 12 of SCN4A gene in the proband. The same mutation was also detect in the proband's father.Conclusions:The heterozygous missense variation of SCN4A gene (p.R672H) found in this study resulted in familial hypokalemic periodic paralysis. Our research provided reference for the future genetic counseling of this patient and enriched the research data on the relationship between genotype and clinical manifestations.
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Current understanding of the genetic factors contributing to the etiology of non-syndromic craniosynostosis (NSC) remains scarce. The present work investigated the presence of variants in ALX4, EFNA4, and TWIST1 genes in children with NSC to verify if variants within these genes may contribute to the occurrence of these abnormal phenotypes. A total of 101 children (aged 45.07±40.94 months) with NSC participated in this cross-sectional study. Parents and siblings of the probands were invited to participate. Medical and family history of craniosynostosis were documented. Biological samples were collected to obtain genomic DNA. Coding exons of human TWIST1, ALX4, and EFNA4 genes were amplified by polymerase chain reaction and Sanger sequenced. Five missense variants were identified in ALX4 in children with bilateral coronal, sagittal, and metopic synostosis. A de novo ALX4 variant, c.799G>A: p.Ala267Thr, was identified in a proband with sagittal synostosis. Three missense variants were identified in the EFNA4 gene in children with metopic and sagittal synostosis. A TWIST1 variant occurred in a child with unilateral coronal synostosis. Variants were predicted to be among the 0.1% (TWIST1, c.380C>A: p. Ala127Glu) and 1% (ALX4, c.769C>T: p.Arg257Cys, c.799G>A: p.Ala267Thr, c.929G>A: p.Gly310Asp; EFNA4, c.178C>T: p.His60Tyr, C.283A>G: p.Lys95Glu, c.349C>A: Pro117Thr) most deleterious variants in the human genome. With the exception of ALX4, c.799G>A: p.Ala267Thr, all other variants were present in at least one non-affected family member, suggesting incomplete penetrance. Thus, these variants may contribute to the development of craniosynostosis, and should not be discarded as potential candidate genes in the diagnosis of this condition.
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Humanos , Criança , Craniossinostoses/genética , Fatores de Transcrição/genética , Sequência de Bases , Família , Estudos Transversais , Mutação de Sentido Incorreto/genética , Proteínas de Ligação a DNA/genéticaRESUMO
Niemann–Pick disease type C (NPC) is a progressive lysosomal storage disorder caused by mutations in the NPC1 (in 95% of cases) or NPC2 (in *5% of cases) genes, inherited in an autosomal recessive manner. We report the case of a 38-year-old woman with learning disorder from her first year of schooling, and could notice slow progressed cognitive impairment, social withdrawal, apathy, handwriting alterations, deterioration of language skills and dysphagia. Brain magnetic resonance imaging showed severe cerebellar atrophy, hypoplasia of the corpus callosum, asymmetric lateral ventricular enlargement, and severe enlargement of frontal and parietal subarachnoid spaces. Next generation sequencing for NPC genes (NPC1 and NPC2) detected compound heterozygous mutations in NPC1 gene, including c.1553G [A (p.Arg518Gln), paternally inherited, and c.1270C [ T (p.Pro424Ser) maternally inherited. The first mutation has been already described in literature and correlated to NPC, while the second mutation is still unknown. Moreover, filipin test and quantification of plasma oxysterols confirmed NPC diagnosis. We can suggest the missense mutation c.1270C [ T (p.Pro424Ser) as a new causative mutation of NPC
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Objective To reveal the pathogenic mutations in Chinese families with idiopathic congenital nystagmus(ICN) Methods Six families with ICN were recruited from Subei People's Hospital. DNA was extracted from peripheral blood samples of all participants. All coding and exon-intronic boundary regions of the targeted gene FRMD7 were amplified with PCR and sequenced using Sanger sequencing to detect potential pathogenic mutations. This study followed the Helsinki Declaration and was approved by the Ethics Committee of Subei People's Hospital (NO. 2015KY-126). All patients or their guardians signed informed consent. Results Three mutations (c. 902A>G, c. 1944T>A and 1945G>T) were screened in two families after co-segregation validation of intrafamilial genotype-phenotype,c. 1944T>A and 1945G>T were newly detected mutations which were not detected in 100 normal controls. No significant mutations were found in the FRMD7 coding region and adjacent splicing sites in the probands of the other four families. Conclusions Two novel pathogenic mutations of FRMD7 are discovered,which expands the pathogenic mutational spectrum of FRMD7 gene causing ICN.
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Objective To analysis the pathogenic mutation and the clinical characteristics of a three generation family with congenital pulverulent cataract. Methods A congenital cataract family was chosen from the First Affiliated Hospital of AnHui Medical University,5 ml peripheral blood was obtained from each family member to extract genomic DNA. Next generation sequencing was used to detect the mutation in proband (Ⅱ5),Ⅱ6 and Ⅲ8, and Sanger sequencing was applied to verify pathogenic mutation in the whole family members. The mutation site was compared with the gene sequence of 10000 normal Chinese. PolyPhen-2 and SIFT were applied to analysis the alteration on the protein structure and function and its possible pathogenesis. This study followed the Declaration of Helsinki and was approved by the Ethics Committee of AnHui Medical University ( NO. PJ2017-5-17 ) . All patients signed informed consent. Results The pedigree consisted of 19 members of three generations,including 10 patients and 9 normal family members. Heterozygous mutation of GJA3 gene c. 427G>A ( p. G143R) was detected in all patients of the pedigree,but was not found in normal members of the pedigree and 10000 normal Chinese. The score calculated from SIFT and PolyPhen-2 indicated that the mutation probably had malignant effect on normal protein structure,Swiss-model website analysis showed that the mutation likely altered the secondary structure of the protein CX 46 by reducing anα-helix between 107-115 amino acids. Meanwhile,c. 1325-1G>T mutation of HSF4 gene were detected in Ⅱ5 and Ⅲ8, which was not found in other family members and 10000 normal Chinese. HSF and MaxEntScan results showed that the mutation probably had serious effect on the splicing of mRNA. The cataract development rates of Ⅱ5 andⅢ8 were faster than that of the same age in the same generation of the pedigree,and the morphology of lens opacity was changed. Conclusions The heterozygous c. 427G>A mutation in GJA3 gene is responsible for pulverulent cataract in this family,meanwhile the c. 1325-1G>T mutation in HSF4 gene may change the type of phacoscotasmus and accelerate the progress of disease.
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Objective@#To reveal the pathogenic mutations in Chinese families with idiopathic congenital nystagmus(ICN)@*Methods@#Six families with ICN were recruited from Subei People's Hospital.DNA was extracted from peripheral blood samples of all participants.All coding and exon-intronic boundary regions of the targeted gene FRMD7 were amplified with PCR and sequenced using Sanger sequencing to detect potential pathogenic mutations.This study followed the Helsinki Declaration and was approved by the Ethics Committee of Subei People's Hospital (NO.2015KY-126). All patients or their guardians signed informed consent.@*Results@#Three mutations (c.902A>G, c.1944T>A and 1945G>T) were screened in two families after co-segregation validation of intrafamilial genotype-phenotype, c.1944T>A and 1945G>T were newly detected mutations which were not detected in 100 normal controls.No significant mutations were found in the FRMD7 coding region and adjacent splicing sites in the probands of the other four families.@*Conclusions@#Two novel pathogenic mutations of FRMD7 are discovered, which expands the pathogenic mutational spectrum of FRMD7 gene causing ICN.
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Objective@#To analysis the pathogenic mutation and the clinical characteristics of a three generation family with congenital pulverulent cataract.@*Methods@#A congenital cataract family was chosen from the First Affiliated Hospital of AnHui Medical University, 5 ml peripheral blood was obtained from each family member to extract genomic DNA.Next generation sequencing was used to detect the mutation in proband (Ⅱ5), Ⅱ6 and Ⅲ8, and Sanger sequencing was applied to verify pathogenic mutation in the whole family members.The mutation site was compared with the gene sequence of 10 000 normal Chinese.PolyPhen-2 and SIFT were applied to analysis the alteration on the protein structure and function and its possible pathogenesis.This study followed the Declaration of Helsinki and was approved by the Ethics Committee of AnHui Medical University (NO.PJ2017-5-17). All patients signed informed consent.@*Results@#The pedigree consisted of 19 members of three generations, including 10 patients and 9 normal family members.Heterozygous mutation of GJA3 gene c. 427G>A (p.G143R) was detected in all patients of the pedigree, but was not found in normal members of the pedigree and 10 000 normal Chinese.The score calculated from SIFT and PolyPhen-2 indicated that the mutation probably had malignant effect on normal protein structure, Swiss-model website analysis showed that the mutation likely altered the secondary structure of the protein CX 46 by reducing an α-helix between 107-115 amino acids.Meanwhile, c.1325-1G>T mutation of HSF4 gene were detected in Ⅱ5 and Ⅲ8, which was not found in other family members and 10 000 normal Chinese.HSF and MaxEntScan results showed that the mutation probably had serious effect on the splicing of mRNA.The cataract development rates of Ⅱ5 and Ⅲ8 were faster than that of the same age in the same generation of the pedigree, and the morphology of lens opacity was changed.@*Conclusions@#The heterozygous c. 427G>A mutation in GJA3 gene is responsible for pulverulent cataract in this family, meanwhile the c. 1325-1G>T mutation in HSF4 gene may change the type of phacoscotasmus and accelerate the progress of disease.
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Objective To explore the clinical phenotype and genotype characteristics of infantile polycystic kidney. Method The clinical data of polycystic kidney disease in one infant were retrospectively analyzed, and the correlation between clinical phenotype and genotype was analyzed. Results In this infant the polycystic kidney was discoved in the fetal period, and shortness of breath, foaming at the mouth were present after birth. Abdominal magnetic resonance imaging indicated that there was medullary sponge kidney in both kidneys accompanied by mild effusion and cysts were found in the right kidney. Gene detection showed a missense mutation c.1123 C>T (Arg375Trp) of exon15 in PKHD1 gene. The exon31 of PKHD1 gene had a missense mutation c.3617G>T (Gly1206Val), which was a new missense mutation. The exon18 of PKD1 gene had a missense mutation c.7211G>A (Arg2404Gln), which is a complex heterozygous mutant of homozygote. All of the mutations are missense mutations. The infant was improved and discharged after treatment, and renal function was normal during 4 months of follow-up. Conclusion Gene detection can be used for early diagnosis of infantile polycystic kidney disease. Newborns with two missense mutations can survive, and exon31 mutation c.3617G>T (Gly1206Val) is a new finding.
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Trichorhinophalangeal syndrome (TRPS) is a rare autosomal dominant hereditary disease caused by mutations in the TRPS1 or the EXT1 gene. Patients show 3 different forms (TRPS I-TRPS III) of this condition sharing similar clinical features including sparse hair, a bulbous nose, an elongated philtrum, short stature, and shortened phalanges. A 10-year-old girl presented with sparse hair and thin hair shafts since birth. She also showed a bulbous nose, an elongated philtrum, brachydactyly of the great toes, and a short stature. Radiological examination showed cone-shaped epiphyses and shortened phalanges. Genetic analysis revealed a novel missense mutation c.2759G>C (p.Trp920Ser) in the TRPS1 gene. We diagnosed this patient with TRPS type III. To our knowledge, only 3 reports have described a genetically analyzed TRPS1 gene mutation among the 11 reported cases of TRPS in the Korean literature. Furthermore, we identified a novel missense mutation in the TRPS1 gene.
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Criança , Feminino , Humanos , Braquidactilia , Epífises , Doenças Genéticas Inatas , Cabelo , Lábio , Mutação de Sentido Incorreto , Nariz , Parto , Dedos do PéRESUMO
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is frequently linked to microtubule abnormalities and mitochondrial trafficking defects. Whole exome sequencing (WES) of patient-parent trios has proven to be an efficient strategy for identifying rare de novo genetic variants responsible for sporadic ALS (sALS). Using a trio-WES approach, we identified a de novo RAPGEF2 variant (c.4069G>A, p.E1357K) in a patient with early-onset sALS. To assess the pathogenic effects of this variant, we have used patient-derived skin fibroblasts and motor neuron-specific overexpression of the RAPGEF2-E1357K mutant protein in Drosophila. Patient fibroblasts display reduced microtubule stability and defective microtubule network morphology. The intracellular distribution, ultrastructure, and function of mitochondria are also impaired in patient cells. Overexpression of the RAPGEF2 mutant in Drosophila motor neurons reduces the stability of axonal microtubules and disrupts the distribution of mitochondria to distal axons and neuromuscular junction (NMJ) synapses. We also show that the recruitment of the pro-apoptotic protein BCL2-associated X (BAX) to mitochondria is significantly increased in patient fibroblasts compared with control cells. Finally, increasing microtubule stability through pharmacological inhibition of histone deacetylase 6 (HDAC6) rescues defects in the intracellular distribution of mitochondria and BAX. Overall, our data suggest that the RAPGEF2 variant identified in this study can drive ALS-related pathogenic effects through microtubule dysregulation.
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Humanos , Esclerose Lateral Amiotrófica , Axônios , Drosophila , Exoma , Fibroblastos , Histona Desacetilases , Microtúbulos , Mitocôndrias , Neurônios Motores , Proteínas Mutantes , Mutação de Sentido Incorreto , Doenças Neurodegenerativas , Junção Neuromuscular , Pele , SinapsesRESUMO
Olmsted syndrome (OS) is a rare congenital skin disorder characterized by severe palmoplantar and periorificial keratoderma, alopecia, onychodystrophy, and severe pruritus. Recently, pathogenic ‘gain-of-function‘ mutations of the transient receptor potential vanilloid 3 gene (TRPV3), which encodes a cation channel involved in keratinocyte differentiation and proliferation, hair growth, inflammation, pain and pruritus, have been identified to cause OS. Due to the rarity, the pattern of inheritance of OS is still unclear. We report a case of OS in a 3-year-old Korean girl and its underlying gene mutation. The patient presented with a disabling, bilateral palmoplantar keratoderma with onychodystrophy. She also exhibited pruritic eczematous skin lesions around her eyes, ears and gluteal fold. Genetic analysis identified a heterozygous p.Gly568Val missense mutation in the exon 13 of TRPV3. To our knowledge, this is the first case of OS in the Korean population showing a missense mutation p.Gly573Ser.
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Pré-Escolar , Feminino , Humanos , Anormalidades Múltiplas/genética , Sequência de Bases , Heterozigoto , Ceratodermia Palmar e Plantar/genética , Gotículas Lipídicas/ultraestrutura , Mutação de Sentido Incorreto/genética , Pele/patologia , Síndrome , Canais de Cátion TRPV/genéticaRESUMO
This paper reported a sporadic case of a 29-year-old Han female diagnosed with tuberous sclerosis complex (TSC) by next generation sequencing (NGS),one of genetic analysis techniques.She was admitted because of recurrent intractable seizure for 26 years,dizziness and headache for 3 months.Physical examination revealed angiofibromas over her face,shagreen patches in her lower back area,and hypomelanotic macules around her limbs and body.Cranial MRI manifested lesions on lateral ventricles,cerebellar vermis and left temporal lobe with abnormal signal changes on both sides of extensive cerebral cortex.A pathogenic and heterozygous missense mutation,c.T1967C,in exon 16 of her TSC1 gene was found via genetic tests,which has not yet been reported before.
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Objective:To analyze the distribution characteristics of IL-13 gene rs20541C/T site polymorphism in Guangxi population and compare the distribution differences among different populations.Methods: IL-13 genotypes were examined by using SNaPshot technique and DNA sequencing in 275 Guangxi people and analyzed the distribution frequencies of allele and genotype in this site.The result compared with the allele and genotype of other populations(Europeans,Beijingers,Japanses and Africans).Results:The polymorphism of rs20541C/T of IL-13 gene in Guangxi population existed.The genotype frequencies of CC,CT and TT were 40.0%,46.2% and 13.8% respectively.The frequencies of C and T allele were found to be 63.1% and 36.9%.The polymorphism had no significant difference between male and female(P>0.05).Compared rs20541C/T of IL-13 gene with those of HapMap-CEU, HapMap-YRI and Tianjin people,the distribution frequency of genotypes was significantly different(P<0.05).In this site,there were significant differences of allele frequency when compared with the other five populations(P<0.05).Conclusion: There are different degrees of diversity of rs20541C/T polymorphism of IL-13 gene among different races and regions.