ABSTRACT
PURPOSE: Congenital contractural arachnodactyly (CCA) is an extremely rare autosomal dominant connective tissue genetic disorder caused by pathogenic variants in FBN2. CCA is characterized by arachnodactyly, camptodactyly, contracture of major joints, scoliosis, pectus deformities, and crumpled ears, but rarely with lethal cardiovascular manifestations as in Marfan syndrome. It is imperative to conduct a comprehensive analysis and review of the pathogenesis of CCA resulting from pathogenic variants in FBN2 gene. MATERIALS AND METHODS: Using whole-exome sequencing and Sanger sequencing, we identified a novel pathogenic splice-altering variant (c.4472-3C>A) in intron 34 of FBN2 gene in a CCA pedigree. The transcriptional result of the splicing-altering variant was analyzed by RNA sequencing. We systematically analyzed the clinical manifestations of all reported cases of CCA caused by splicing-altering pathogenic variants and focused on all the pathogenic variants in FBN2 gene that are associated with severe cardiovascular manifestations. RESULTS: The splice-altering variant (c.4472-3C>A) in FBN2 was demonstrated to result in the exon 35 skipping and cause an in-frame deletion. Furthermore, we identified exons 31 to 35 may be a hotspot region in FBN2 gene associated with severe cardiovascular phenotype. CONCLUSIONS: This study enriched the pathogenic spectrum of CCA and identified a hotspot region in FBN2 gene associated with severe cardiovascular manifestations. We recommend that patients carrying pathogenic variants in exons 31 to 35 of FBN2 pay more attention to cardiac evaluation.
Subject(s)
Arachnodactyly , Contracture , Fibrillin-2 , Fibrillin-2/genetics , Humans , Arachnodactyly/genetics , Arachnodactyly/pathology , Contracture/genetics , Contracture/pathology , Male , Female , Pedigree , MutationABSTRACT
BACKGROUND: The bicuspid aortic valve (BAV) is prone to ascending aortic dilatation (AAD) involving both the tubular segment and the aortic root. The genetic factor was proposed as one of the most important mechanisms for AAD. We hypothesized that the rare genetic variants mainly contribute to the pathogenesis of aortic roots in affected individuals. METHODS: The diameter of aortic root or ascending aorta ≥ 40 mm was counted as AAD. The targeted next-generation sequencing of 13 BAV-associated genes were performed on a continuous cohort of 96 unrelated BAV patients. The rare variants with allele frequency < 0.05% were selected and analyzed. Variants frequency was compared against the Exome aggregation consortium database. The pathogenicity of the genetic variants was evaluated according to the American College of Medical Genetics and Genomics guidelines. RESULTS: A total of 27 rare nonsynonymous coding variants involving 9 genes were identified in 25 individuals. The burden analysis revealed that variants in GATA5, GATA6, and NOTCH1 were significantly associated with BAV. Eighty percent of the pathogenic variants were detected in root group. The detection rate of rare variants was higher in root dilatation group (71.4%) compared with normal aorta (29.0%) and tubular dilatation groups (29.6%) (P = 0.018). The rare variant was identified as the independent risk factor of root dilatation [P = 0.014, hazard ratio = 23.9, 95% confidence interval (1.9-302.9)]. CONCLUSIONS: Our results presented a broad genetic spectrum in BAV patients. The rare variants of BAV genes contribute the most to the root phenotype among BAV patients.
Subject(s)
Aortic Aneurysm/genetics , Bicuspid Aortic Valve Disease/genetics , Genetic Variation , Adolescent , Adult , Aged , Aortic Aneurysm/diagnostic imaging , Bicuspid Aortic Valve Disease/complications , Bicuspid Aortic Valve Disease/diagnostic imaging , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Heredity , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Phenotype , Risk Assessment , Risk Factors , Young AdultABSTRACT
BACKGROUND: Although studies have identified hundreds of genetic variants associated with asthma risk, a large fraction of heritability remains unexplained, especially in Chinese individuals. METHODS: To identify genetic risk factors for asthma in a Han Chinese population, 211 asthma-related genes were first selected based on database searches. The genes were then sequenced for subjects in a Discovery Cohort (284 asthma patients and 205 older healthy controls) using targeted next-generation sequencing. Bioinformatics analysis and statistical association analyses were performed to reveal the associations between rare/common variants and asthma, respectively. The identified common risk variants underwent a validation analysis using a Replication Cohort (664 patients and 650 controls). RESULTS: First, we identified 18 potentially functional rare loss-of-function (LOF) variants in 21/284 (7.4%) of the asthma cases. Second, using burden tests, we found that the asthma group had nominally significant (p < 0.05) burdens of rare nonsynonymous variants in 10 genes. Third, 23 common single-nucleotide polymorphisms were associated with the risk of asthma, 7/23 (30.4%) and 9/23 (39.1%) of which were modestly significant (p < 9.1 × 10-4 ) in the Replication Cohort and Combined Cohort, respectively. According to our cumulative risk model involving the modestly associated alleles, middle- and high-risk subjects had a 2.0-fold (95% CI: 1.621-2.423, p = 2.624 × 10-11 ) and 6.0-fold (95% CI: 3.623-10.156, p = 7.086 × 10-12 ) increased risk of asthma, respectively, compared with low-risk subjects. CONCLUSION: This study revealed novel rare and common genetic risk factors for asthma, and provided a cumulative risk model for asthma risk prediction and stratification in Han Chinese individuals.
Subject(s)
Asthma/genetics , Asthma/pathology , Biomarkers/metabolism , Genetic Predisposition to Disease , High-Throughput Nucleotide Sequencing/methods , Polymorphism, Single Nucleotide , Adolescent , Adult , Aged , Aged, 80 and over , Asthma/epidemiology , Biomarkers/analysis , Case-Control Studies , Child , Child, Preschool , China/epidemiology , Cohort Studies , Female , Follow-Up Studies , Genome-Wide Association Study , Humans , Infant , Infant, Newborn , Male , Middle Aged , Prognosis , Young AdultABSTRACT
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a genetic heterogeneous disease with high mortality and poor prognosis. Hyaluronidase 1 (HYAL1) was found to be upregulated in fibroblasts from IPF patients, and overexpression of HYAL1 could prevent human fetal lung fibroblast proliferation. However, the genetic correlation between the HYAL1 and IPF or connective tissue diseases related interstitial lung disease (CTD-ILD) has not been determined. METHODS: A two-stage study was conducted in Southern Han Chinese population. We sequenced the coding regions and flanking regulatory regions of HYAL1 in stage one (253 IPF cases and 125 controls). A statistically significant variant was further genotyped in stage two (162 IPF cases, 182 CTD-ILD cases, and 225 controls). RESULTS: We identified a nonsynonymous polymorphism (rs117179004, T392M) significantly associated with increased IPF risk (dominant model: OR = 2.239, 95% CI = 1.212-4.137, p = 0.010 in stage one; OR = 2.383, 95% CI = 1.376-4.128, p = 0.002 in stage two). However, we did not observe this association in CTD-ILD (OR = 1.401, 95% CI = 0.790-2.485, p = 0.248). CONCLUSION: Our findings suggest that the nonsynonymous polymorphism (rs117179004, T392M) may confer susceptibility to IPF in Southern Han Chinese, but is not associated with susceptibility to CTD-ILD.
Subject(s)
Hyaluronoglucosaminidase/genetics , Idiopathic Pulmonary Fibrosis/genetics , Polymorphism, Single Nucleotide , Aged , Asian People/genetics , Case-Control Studies , Female , Gene Frequency , Genetic Predisposition to Disease , Humans , Lung Diseases, Interstitial/genetics , Male , Middle AgedABSTRACT
BACKGROUND: Autosomal dominant hypertension with brachydactyly type E syndrome caused by pathogenic variants in the PDE3A gene was first reported in 2015. To date, there are only a few reports of this kind of syndrome. Other patients still lack a genetic diagnosis. CASE PRESENTATION: Whole-exome sequencing was performed in an 18-year-old female proband with a clinical diagnosis of hypertension with brachydactyly syndrome. Quantitative real-time PCR was used to identify pathogenic copy number variations (CNVs). After bioinformatics analysis and healthy control database filtering, we revealed a heterozygous missense PDE3A variant (c.1346G > A, p.Gly449Asp). The variant was absent in the ExAC database and located in a highly evolutionarily conserved cluster of reported PDE3A pathogenic variants. Importantly, this variant was predicted to affect protein function by both SIFT (score = 0) and PolyPhen-2 (score = 1). After Sanger sequencing, the variant was determined to be absent in the healthy parents of the proband as well as 800 ethnically and geographically matched healthy controls. CONCLUSION: We present a report linking a de novo PDE3A variant to autosomal dominant hypertension with brachydactyly type E syndrome.
Subject(s)
Brachydactyly/genetics , Cyclic Nucleotide Phosphodiesterases, Type 3/genetics , Exome Sequencing , Genes, Dominant , Hypertension/congenital , Mutation/genetics , Adolescent , Brachydactyly/diagnostic imaging , Exons/genetics , Female , Humans , Hypertension/diagnostic imaging , Hypertension/genetics , Male , Pedigree , SyndromeABSTRACT
Brugada syndrome (BrS) is a known cause of sudden cardiac death (SCD) characterized by abnormal electrocardiograms and fatal arrhythmias. The variants in KCND3 encoding the KV4.3 potassium-channel (the α-subunit of the Ito) have seldom been reported in BrS. This study aimed to identify novel KCND3 variants associated with BrS and elucidate BrS pathogenesis. High-depth targeted sequencing was performed and the electrophysiological properties of the variants were detected by whole-cell patch-clamp methods in a cultured-cell expressing system. The transcriptional levels of KV4.3 in different genotypes were studied by real-time PCR. Western blot was used to assess channel protein expression. A novel KCND3heterozygous variant, c.1292G>A (Arg431His, R431H), was found in the proband. Whole-cell patch-clamp results revealed a gain-of-function phenotype in the variant, with peak Ito current density increased and faster recovery from inactivation. The expression of mutant Kv4.3 membrane protein increased and the cytoplasmic protein decreased, demonstrating that the membrane/cytoplasm ratio was significantly different. In conclusion, a novel KCND3 heterozygous variant was associated with BrS. The increased Ito current explained the critical role of KCND3 in the pathogenesis of BrS. Genetic screening for KCND3 could be useful for understanding the pathogenesis of BrS and providing effective risk stratification in the clinic.
Subject(s)
Brugada Syndrome , Shal Potassium Channels , Brugada Syndrome/genetics , Death, Sudden, Cardiac , Gain of Function Mutation , Humans , Mutation , Patch-Clamp Techniques , Shal Potassium Channels/geneticsABSTRACT
Isolated hypogonadotropic hypogonadism (IHH) is a rare but treatable form of male infertility caused by congenital defect in gonadotropin-releasing hormone (GnRH) secretion or action. We report a Chinese IHH male with a novel FGFR1 mutation who successfully fathered a normal son. Targeted next-generation sequencing, bioinformatics analysis and Sanger sequencing were performed by using the DNA extracted from the pedigree. The patient was treated with gonadotropin and was able to impregnant his wife during the treatment. Amniocentesis was performed at the 18 weeks of gestation. A novel de novo pathogenic missense variant (c.980A>G, p.Asn327Ser) in exon 8 in FGFR1 gene (NM_001174067.1) was identified in the patient but not in his normal parents. This variant was also absent in the DNA obtained from the amniocentesis sample. His son has normal growth and development at the age of 2 years. This is the first case of prenatal genetic diagnosis based on the genetic testing of the IHH father by combining targeted next-generation and Sanger sequencing in IHH family. We extended the mutation spectrum of FGFR1 in IHH patients. Prenatal genetic diagnosis based on the results of genetic testing of the IHH patients may be helpful in the genetic counselling for the IHH families.
Subject(s)
Fathers , Hypogonadism , Receptor, Fibroblast Growth Factor, Type 1 , Child, Preschool , Gonadotropin-Releasing Hormone , Humans , Hypogonadism/diagnosis , Hypogonadism/genetics , Male , Mutation , Pedigree , Receptor, Fibroblast Growth Factor, Type 1/geneticsABSTRACT
BACKGROUND: Hereditary sensory and autonomic neuropathy (HSAN) type II is a group of extremely rare autosomal recessive neurological disorders with heterogeneous clinical and genetic characteristics. METHODS: We performed high-depth next-generation targeted sequencing using a custom-ordered "HSAN" panel, covering WNK1, NTRK1, NGF, SPTLC1 and IKBKAP genes, to identify pathogenic variants of the proband as well as the family members. We also performed whole exome sequencing to further investigate the potential occurrence of additional pathogenic variants in genes that were not covered by the "HSAN" panel. Quantitative real-time PCR was used to identify pathogenic copy number variations (CNVs) and to analyze the mRNA level of WNK1 gene of the family. Western blot analysis was performed to evaluate the WNK1 protein expression level. RESULTS: After sequencing, a novel nonsense variant (c.2747 T > G, p.Leu916Ter) in exon 9 of WNK1 gene was identified in two patients (hemizygous) and their mother (heterozygous). This variant is absent in all public databases as well as in 600 Han Chinese healthy controls. The region of this variant is evolutionary highly conserved. Furthermore, by quantitative real-time PCR using DNA of the pedigree, we revealed a large deletion containing the whole WNK1 gene in two patients. The WNK1 expression levels of the patients were significantly reduced. CONCLUSIONS: Our study firstly revealed that the coexistence of a novel WNK1 nonsense variant and a CNV resulted in HSAN type IIA in a Han Chinese family.
Subject(s)
Codon, Nonsense , DNA Copy Number Variations , Hereditary Sensory and Autonomic Neuropathies/genetics , WNK Lysine-Deficient Protein Kinase 1/genetics , Amino Acid Sequence , Base Sequence , DNA Mutational Analysis , Family Health , Female , Hereditary Sensory and Autonomic Neuropathies/metabolism , Hereditary Sensory and Autonomic Neuropathies/pathology , High-Throughput Nucleotide Sequencing/methods , Humans , Male , Pedigree , Sequence Homology, Amino Acid , WNK Lysine-Deficient Protein Kinase 1/metabolismABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a genetic heterogeneous disease with high mortality and poor prognosis. However, a large fraction of genetic cause remains unexplained, especially in sporadic IPF (â¼80% IPF). By systemically reviewing related literature and potential pathogenic pathways, 92 potentially IPF-related genes were selected and sequenced in genomic DNAs from 253 sporadic IPF patients and 125 matched health controls using targeted massively parallel next-generation sequencing. The identified risk variants were confirmed by Sanger sequencing. We identified two pathogenic and 10 loss-of-function (LOF) candidate variants, accounting for 4.74% (12 out of 253) of all the IPF cases. In burden tests, rare missense variants in three genes (CSF3R, DSP, and LAMA3) were identified that have a statistically significant relationship with IPF. Four common SNPs (rs3737002, rs2296160, rs1800470, and rs35705950) were observed to be statistically associated with increased risk of IPF. In the cumulative risk model, high risk subjects had 3.47-fold (95%CI: 2.07-5.81, P = 2.34 × 10-6 ) risk of developing IPF compared with low risk subjects. We drafted a comprehensive map of genetic risks (including both rare and common candidate variants) in patients with IPF, which could provide insights to help in understanding mechanisms, providing genetic diagnosis, and predicting risk for IPF.
Subject(s)
Desmoplakins/genetics , Idiopathic Pulmonary Fibrosis/genetics , Laminin/genetics , Receptors, Colony-Stimulating Factor/genetics , Female , Genetic Predisposition to Disease , Genome, Human/genetics , Genome-Wide Association Study , High-Throughput Nucleotide Sequencing , Humans , Male , Mutation, Missense/genetics , Polymorphism, Single Nucleotide/genetics , Risk Factors , Signal Transduction/geneticsSubject(s)
Cardiology , Cardiomyopathies , Genetics, Medical , Cardiomyopathies/diagnosis , Cardiomyopathies/genetics , Consensus , Genomics , Humans , Phenotype , United StatesABSTRACT
BACKGROUND: Rapidly determining the complex genetic basis of Hypertrophic cardiomyopathy (HCM) is vital to better understanding and optimally managing this common polygenetic cardiovascular disease. METHODS: A rapid custom Ion-amplicon-resequencing assay, covering 30 commonly affected genes of HCM, was developed and validated in 120 unrelated patients with HCM to facilitate genetic diagnosis of this disease. With this HCM-specific panel and only 20 ng of input genomic DNA, physicians can, for the first time, go from blood samples to variants within a single day. RESULTS: On average, this approach gained 595628 mapped reads per sample, 95.51% reads on target (64.06 kb), 490-fold base coverage depth and 93.24% uniformity of base coverage in CDS regions of the 30 HCM genes. After validation, we detected underlying pathogenic variants in 87% (104 of 120) samples. Tested seven randomly selected HCM genes in eight samples by Sanger sequencing, the sensitivity and false-positive-rate of this HCM panel was 100% and 5%, respectively. CONCLUSIONS: This Ion amplicon HCM resequencing assay provides a currently most rapid, comprehensive, cost-effective and reliable measure for genetic diagnosis of HCM in routinely obtained samples.
Subject(s)
Cardiomyopathy, Hypertrophic/diagnosis , Molecular Diagnostic Techniques , Semiconductors , Sequence Analysis, DNA/methods , Cardiomyopathy, Hypertrophic/genetics , Humans , MutationABSTRACT
Population aging and carbon emissions are critical issues for China's development. As an enormous complex system, the population and the carbon emission development process have non-negligible differences in time, space, and speed. Therefore, this paper first demonstrates the spatial and temporal correlation between population aging and carbon emissions from 1995 to 2020, then uses the allometric growth analysis model to make a cross-sectional temporal comparison and a vertical spatial comparison of the relationship and development rate of the two, and finally uses the ridge regression model to determine the forces and interaction mechanisms of the factors influencing the relationship between population aging and carbon emissions at allometric rates. The results show that (1) China has a long-term positive temporal correlation effect relationship between population aging and carbon emissions from 1995 to 2020, and the overall correlation is high. The spatial correlation intensity between population aging and carbon emissions varies significantly across Chinese provinces, with a general spatial distribution trend of high in the south, low in the north, and prominent in the center. (2) China's population aging and carbon emissions mainly show a negative allometric growth type of relationship, i.e., a strong trend of population aging expansion and a strengthening trend of carbon emission system shrinking. The number of provinces with negative allometric growth is gradually increasing, mainly in North, East, Central, and Southwest China. (3) From 1995-2010 period to the 2011-2020 period, the influence of the factors of the population, production, and economic dimensions on the population aging index and the carbon emission allometric scalar index gradually weakened, and the influence of the consumption and technology dimensions increased significantly. The factors on the population and consumption side of the dimension mainly contribute to the expansion of carbon emissions and drive positive allometric growth. The production side, the economic structure, and technology dimension factors drive negative allometric growth. The paper fully explores the bidirectional correlation, differential development trend, and interaction mechanism between the two systems of population and carbon emissions and effectively compensates for the lack of research content in terms of elemental correlation, spatial and temporal connection, and speed synergy.
Subject(s)
Aging , Asian People , Humans , Cross-Sectional Studies , Carbon , China , Carbon Dioxide , Economic DevelopmentABSTRACT
The oocyte maturation defect 6 is an autosomal recessive hereditary disease caused by a homozygous variant in ZP2 gene. It is characterized by female primary infertility due to an abnormally thin zona pellucida (ZP) and defective sperm binding. Here we identified a compound heterozygous variant (c.1924C > T and c.1695-2A > G) in ZP2 gene in a Chinese Han family. Quantitative real-time PCR showed that the variant c.1924C > T significantly decreased the expression of truncated ZP2 message RNA by the nonsense-mediated decay pathway. Minigene assays showed the c.1695-2A > G variant led to an extra-61-nt preservation of intron 15 at the junction between exons 15 and 16 during transcription. Both variants (c.1924C > T and c.1695-2A > G) resulted in truncated ZP2 proteins (p.R642X and p.C566Hfs*2) that lost the transmembrane domain, which prevented the secretion of the mutant ZP2 proteins and produced a structurally abnormal ZP, thus resulting in female infertility. This study further elucidated the pathogenic mechanism of these two variants and provided new support for the genetic diagnosis of female infertility.
ABSTRACT
BACKGROUND: Waardenburg syndrome type 2 (WS2) has been reported to be a rare hereditary disorder, which is distinguished by vivid blue eyes, varying degrees of hearing impairment, and abnormal pigment deposition in the skin and hair. Variants in the sex-determining region Y-box containing gene 10 (SOXl0) gene may cause congenital deafness and have been demonstrated to be important during the development of WS2. METHODS: Complete clinical data of the proband and her family members (her parents and 2 sisters) was collected and physical examinations were performed in the hospital. The laboratory examination including hemoglobin, Coomb's test, urine protein, ENA, autoimmune hepatitis-related autoantibodies and ultrasonography were all conducted. We obtained the peripheral blood samples from all the participants and performed whole exome sequencing and sanger sequencing validation. RESULTS: The present study identified a family of 5 members, and only the proband exhibited typical WS2. Beyond the characteristics of WS2, the proband also manifested absence of puberty. The proband and her younger sister manifested systemic lupus erythematosus (SLE). Whole exome sequencing revealed a de novo variant in the SOX10 gene. The variant c.175 C > T was located in exon 2 of the SOX10 gene, which is anticipated to result in early termination of protein translation. CONCLUSION: The present study is the first to report a case of both WS2 and SLE, and the present findings may provide a new insight into WS2.
Subject(s)
Pedigree , SOXE Transcription Factors , Waardenburg Syndrome , Humans , Waardenburg Syndrome/genetics , SOXE Transcription Factors/genetics , Female , Male , Adult , Exome Sequencing , MutationABSTRACT
The quest for advanced water purification technologies has been vigorous over recent decades, motivated by the promise of ever more efficient, greener, and affordable tools. Halloysite nanotubes (HNTs) are naturally-occurring materials that have shown potential as dye sorbents. Unfortunately, these nanoclays suffer from low permeation during water treatment, which limits their widespread application. Here, we use cellulose nanocrystals (CNCs) as structural scaffolds to support HNTs and fabricate permeable aerogel sorbent materials with mechanical stability. Aerogels containing 40 wt% HNTs showed a maximum dye adsorption capacity of 60 mg g-1 towards methylene blue, with only 15% decay in efficiency after 5 cycles. The good mechanical properties of these materials allowed for their incorporation into free-flowing purification columns that displayed excellent dye removal ability. Overall, this work provides a new strategy to fabricate green, renewable, and low-cost sorbent materials for the removal of dyes and shows potential for the sorption of other ionic pollutants.
ABSTRACT
Gels are useful materials for drug delivery, wound dressings, tissue engineering, and 3D printing. These various applications require gels with different mechanical properties that can be easily tuned, also preferably excluding the use of chemical additives, which can be toxic or harmful to the body or environment. Here, we report a novel strategy to synthesize cellulose nanocrystal (CNC) gels with tunable mechanical properties. Sequential freeze-thaw cycling and hydrothermal treatments were applied to CNC suspensions in different orders to give a series of pristine CNC hydrogels. Freeze-drying of the hydrogels also afforded a series of lightweight CNC aerogels. The mechanical properties of the hydrogels and aerogels were studied by rheological measurements and compression strength tests, respectively. Specifically, the complex modulus of CNC hydrogels ranged from 160 to 32,000 Pa among eight different hydrogels, while Young's modulus of CNC aerogels was tuned from 0.114 to 3.98 MPa across five different aerogels. The microstructures of aerogels were also investigated by scanning electron microscopy and X-ray microtomography, which revealed remarkable differences between the materials. Solvent sorption-desorption tests showed that the reinforced networks have excellent stability over the basic CNC aerogels in ethanol, demonstrating a material enhancement from the preparation strategies we developed. Thermal conductivity and thermal stability for these materials were also investigated, and it was found that the lowest thermal conductivity was 0.030 W/m K, and all of the aerogels are generally stable below 280 °C. These characteristics also expand the potential applications of this family of CNC gels to lightweight supporting materials and thermal insulators.
ABSTRACT
Previous studies have revealed that patients with hypertrophic cardiomyopathy (HCM) exhibit differences in symptom severity and prognosis, indicating potential HCM subtypes among these patients. Here, 793 patients with HCM were recruited at an average follow-up of 32.78 ± 27.58 months to identify potential HCM subtypes by performing consensus clustering on the basis of their echocardiography features. Furthermore, we proposed a systematic method for illustrating the relationship between the phenotype and genotype of each HCM subtype by using machine learning modeling and interactome network detection techniques based on whole-exome sequencing data. Another independent cohort that consisted of 414 patients with HCM was recruited to replicate the findings. Consequently, two subtypes characterized by different clinical outcomes were identified in HCM. Patients with subtype 2 presented asymmetric septal hypertrophy associated with a stable course, while those with subtype 1 displayed left ventricular systolic dysfunction and aggressive progression. Machine learning modeling based on personal whole-exome data identified 46 genes with mutation burden that could accurately predict subtype propensities. Furthermore, the patients in another cohort predicted as subtype 1 by the 46-gene model presented increased left ventricular end-diastolic diameter and reduced left ventricular ejection fraction. By employing echocardiography and genetic screening for the 46 genes, HCM can be classified into two subtypes with distinct clinical outcomes.
ABSTRACT
BACKGROUND: Tumor necrosis factor-α (TNF-α) is one of the most typical pro-inflammatory cytokines with both beneficial and destructive properties for the central nervous system. Increasing evidences have demonstrated the important role of TNF-α in the development of ischemic stroke, but studies examining the possible association with stroke or direct functional effects of polymorphisms in TNF-α have been contradictory. FINDINGS: In this study, a 2-kb length of the proximal promoter of the TNF-α was screened and four polymorphisms were investigated in the case-control study. Our data confirmed the association between -308G/A variant with stroke in 1,388 stroke patients and 1,027 controls and replicated in an independent population of 961 stroke patients and 821 controls (odds ratio (OR) = 1.34, 95% confidence interval (CI) =1.02 to 1.77 and OR = 1.56, 95% CI = 1.09 to 2.23, respectively). To reconcile the association between polymorphisms and stroke and to give a comprehensive picture of the genetic architecture of this important gene, we performed a meta-analysis of 15 published studies in an Asian population. Our results demonstrated an association between rs1800629 and ischemic stroke (OR = 1.43, 95% CI = 1.21 to 1.69). Another meta-analysis results of 14 studies demonstrated that ischemic stroke patients have higher serum TNF-α level than the control subjects (standardized mean difference (SMD) = 2.33, 95% CI = 1.85 to 2.81). In vitro evaluation of potential interaction between variants of the TNF-α gene (-308G/A, -857C/T, and -1031T/C) demonstrated that these three polymorphisms could interact together to determine the overall activity of the TNF-α gene. CONCLUSIONS: These findings strongly implicate the involvement of TNF-α in the pathogenesis of stroke.
Subject(s)
Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Promoter Regions, Genetic/genetics , Stroke/genetics , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/genetics , Adult , Aged , Case-Control Studies , Cell Line, Transformed , Cohort Studies , Female , Gene Frequency , Genetic Linkage , Genotype , Humans , Ischemia/complications , Male , Meta-Analysis as Topic , Middle Aged , Risk Factors , Stroke/blood , Stroke/epidemiology , Stroke/etiology , TransfectionABSTRACT
Marfan syndrome (MFS) is a life-threatening autosomal dominant genetic disorder of connective tissue caused by the pathogenic mutation of FBN1. Whole exome sequencing and Sanger sequencing were performed to identify the pathogenic mutation. The transcriptional consequence of the splice-altering mutation was analyzed via minigene assays and reverse-transcription PCR. We identified a novel pathogenic mutation (c.8051+1G>C) in the splice site of exon 64 of the FBN1 gene in an MFS-pedigree. This mutation was confirmed to cause two different truncated transcripts (entire exon 64 skipping; partial exon 64 exclusion). We also systematically summarized previously reported transcriptional studies of pathogenic splice-altering mutations in the FBN1 gene to investigate the clinical and transcriptional consequences. In conclusion, we reported for the first time that a splice-altering mutation in the FBN1 gene leads to two abnormal transcripts simultaneously.
Subject(s)
Marfan Syndrome , Humans , Marfan Syndrome/genetics , Marfan Syndrome/pathology , Fibrillin-1/genetics , DNA Mutational Analysis , Mutation , PedigreeABSTRACT
Aortic dissection (AD) is a cardiovascular disease characterized by high mortality and poor prognosis. Although FBN1 is associated with syndromic AD, its association with non-syndromic AD remains unclear. In this study, DNA samples from 90 Chinese individuals with non-syndromic AD (60 Stanford A, 30 Stanford B types) were analyzed to determine the relationship between diverse genotypes of the FBN1 gene and non-syndromic AD. Eleven pathogenic/likely pathogenic variants (1 novel) were identified in 12.2% of patients with non-syndromic AD. Patients with positive variants suffered from AD at a younger age than those in the negative variant group. Among the six positive missense mutations associated with cysteine residue hosts, four (66.7%) were Stanford A AD, whereas two (33.3%) were Stanford B AD. Three (100%) positive splicing/truncation variant hosts were Stanford A AD. The splicing/truncation variants and missense variants involving cysteine residues in the FBN1 gene increased the risk of Stanford A AD. Ten common SNPs that increased susceptibility to AD were identified. In particular, five SNPs were detected significantly in Stanford A AD, whereas another four SNPs were significantly detected in Stanford B AD. These significant variants can function as biomarkers for the identification of patients at risk for AD. Our findings have the potential to broaden the database of positive mutations and common SNPs of FBN1 in non-syndromic AD among the Chinese population.