Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 374
Filtrar
1.
Clin Genet ; 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619735

RESUMO

Up to 40% of neurodevelopmental disorders (NDDs) such as intellectual disability, developmental delay, autism spectrum disorder, and developmental motor abnormalities have a documented underlying monogenic defect, primarily due to de novo variants. Still, the overall burden of de novo variants as well as novel disease genes in NDDs await discovery. We performed parent-offspring trio exome sequencing in 231 individuals with NDDs. Phenotypes were compiled using human phenotype ontology terms. The overall diagnostic yield was 49.8% (n = 115/231) with de novo variants contributing to more than 80% (n = 93/115) of all solved cases. De novo variants affected 72 different-mostly constrained-genes. In addition, we identified putative pathogenic variants in 16 genes not linked to NDDs to date. Reanalysis performed in 80 initially unsolved cases revealed a definitive diagnosis in two additional cases. Our study consolidates the contribution and genetic heterogeneity of de novo variants in NDDs highlighting trio exome sequencing as effective diagnostic tool for NDDs. Besides, we illustrate the potential of a trio-approach for candidate gene discovery and the power of systematic reanalysis of unsolved cases.

2.
Circulation ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33550817

RESUMO

Background: Cardiac macrophages (cMP) are increasingly recognized as important regulators of myocardial homeostasis and disease, yet the role of noncoding RNA in these cells is largely unknown. Small RNA sequencing of the entire miRNomes of the major cardiac cell fractions revealed microRNA-21 (miR-21) as the single highest expressed microRNA in cMPs, both in health and disease (25% and 43% of all microRNA reads respectively). MiR-21 has been previously reported as a key microRNA driving tissue fibrosis. Here, we aimed to determine the function of macrophage miR-21 on myocardial homeostasis and disease-associated remodeling. Methods: Macrophage-specific ablation of miR-21 in mice driven by Cx3cr1-Cre was used to determine the function of miR-21 in this cell type. As a disease model, mice were subjected to pressure overload for 6 and 28 days. Cardiac function was assessed in vivo by echocardiography, followed by histological analyses and single cell sequencing. Co-cultures of macrophages and cardiac fibroblasts were employed to study macrophage-to-fibroblast signaling. Results: Mice with macrophage-specific genetic deletion of miR-21 were protected from interstitial fibrosis and cardiac dysfunction when subjected to pressure overload of the left ventricle. Single cell sequencing of pressure-overloaded hearts from these mice revealed that miR-21 in macrophages is essential for their polarization towards a M1-like phenotype. Systematic quantification of intercellular communication mediated by ligand-receptor interactions across all cell types revealed that miR-21 primarily determined macrophage-fibroblast communication, promoting the transition from quiescent fibroblasts to myofibroblasts. Polarization of isolated macrophages in vitro towards a pro-inflammatory (M1) phenotype activated myofibroblast transdifferentiation of cardiac fibroblasts in a paracrine manner and was dependent on the rapid induction of miR-21 in cMPs. Conclusions: Our data indicate a critical role of cMPs in pressure overload-induced cardiac fibrosis and dysfunction and reveal macrophage miR-21 as a key molecule for the pro-fibrotic role of cMPs.

4.
Brain ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33459760

RESUMO

The von Willebrand Factor A domain containing 1 protein, encoded by VWA1, is an extracellular matrix protein expressed in muscle and peripheral nerve. It interacts with collagen VI and perlecan, two proteins that are affected in hereditary neuromuscular disorders. Lack of VWA1 is known to compromise peripheral nerves in a Vwa1 knock-out mouse model. Exome sequencing led us to identify bi-allelic loss of function variants in VWA1 as the molecular cause underlying a so far genetically undefined neuromuscular disorder. We detected six different truncating variants in 15 affected individuals from six families of German, Arabic, and Roma descent. Disease manifested in childhood or adulthood with proximal and distal muscle weakness predominantly of the lower limbs. Myopathological and neurophysiological findings were indicative of combined neurogenic and myopathic pathology. Early childhood foot deformity was frequent, but no sensory signs were observed. Our findings establish VWA1 as a new disease gene confidently implicated in this autosomal recessive neuromyopathic condition presenting with child-/adult-onset muscle weakness as a key clinical feature.

5.
Nat Genet ; 53(2): 128-134, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33495596

RESUMO

The heart muscle diseases hypertrophic (HCM) and dilated (DCM) cardiomyopathies are leading causes of sudden death and heart failure in young, otherwise healthy, individuals. We conducted genome-wide association studies and multi-trait analyses in HCM (1,733 cases), DCM (5,521 cases) and nine left ventricular (LV) traits (19,260 UK Biobank participants with structurally normal hearts). We identified 16 loci associated with HCM, 13 with DCM and 23 with LV traits. We show strong genetic correlations between LV traits and cardiomyopathies, with opposing effects in HCM and DCM. Two-sample Mendelian randomization supports a causal association linking increased LV contractility with HCM risk. A polygenic risk score explains a significant portion of phenotypic variability in carriers of HCM-causing rare variants. Our findings thus provide evidence that polygenic risk score may account for variability in Mendelian diseases. More broadly, we provide insights into how genetic pathways may lead to distinct disorders through opposing genetic effects.

6.
Clin Epigenetics ; 13(1): 7, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413638

RESUMO

BACKGROUND: The discovery of robust and trans-ethnically replicated DNA methylation markers of metabolic phenotypes, has hinted at a potential role of epigenetic mechanisms in lipid metabolism. However, DNA methylation and the lipid compositions and lipid concentrations of lipoprotein sizes have been scarcely studied. Here, we present an epigenome-wide association study (EWAS) (N = 5414 total) of mostly lipid-related metabolic measures, including a fine profiling of lipoproteins. As lipoproteins are the main players in the different stages of lipid metabolism, examination of epigenetic markers of detailed lipoprotein features might improve the diagnosis, prognosis, and treatment of metabolic disturbances. RESULTS: We conducted an EWAS of leukocyte DNA methylation and 226 metabolic measurements determined by nuclear magnetic resonance spectroscopy in the population-based KORA F4 study (N = 1662) and replicated the results in the LOLIPOP, NFBC1966, and YFS cohorts (N = 3752). Follow-up analyses in the discovery cohort included investigations into gene transcripts, metabolic-measure ratios for pathway analysis, and disease endpoints. We identified 161 associations (p value < 4.7 × 10-10), covering 16 CpG sites at 11 loci and 57 metabolic measures. Identified metabolic measures were primarily medium and small lipoproteins, and fatty acids. For apolipoprotein B-containing lipoproteins, the associations mainly involved triglyceride composition and concentrations of cholesterol esters, triglycerides, free cholesterol, and phospholipids. All associations for HDL lipoproteins involved triglyceride measures only. Associated metabolic measure ratios, proxies of enzymatic activity, highlight amino acid, glucose, and lipid pathways as being potentially epigenetically implicated. Five CpG sites in four genes were associated with differential expression of transcripts in blood or adipose tissue. CpG sites in ABCG1 and PHGDH showed associations with metabolic measures, gene transcription, and metabolic measure ratios and were additionally linked to obesity or previous myocardial infarction, extending previously reported observations. CONCLUSION: Our study provides evidence of a link between DNA methylation and the lipid compositions and lipid concentrations of different lipoprotein size subclasses, thus offering in-depth insights into well-known associations of DNA methylation with total serum lipids. The results support detailed profiling of lipid metabolism to improve the molecular understanding of dyslipidemia and related disease mechanisms.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33259146

RESUMO

Coiled-Coil Domain Containing Protein 186 (CCDC186) is hypothesized to play an important role in the biogenesis of dense-core vesicles in neurons and endocrine cells. Biallelic loss-of-function variants in the encoding gene CCDC186 have been suggested as a candidate gene for a neurodevelopmental phenotype, but only one patient has been described so far. We report a second patient with a CCDC186-associated phenotype presenting with developmental delay, epileptic encephalopathy, and failure to thrive. Exome sequencing identified a homozygous loss-of-function variant in CCDC186 (NM_018017.2) c.767C> G; p.(Ser256Ter) thus providing further evidence to support CCDC186 as a new disease gene for an autosomal recessive neurodevelopmental disorder.

8.
Brain ; 2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33313762

RESUMO

Claudin-11, a tight junction protein, is indispensable in the formation of the radial component of myelin. Here, we report de novo stop-loss variants in the gene encoding claudin-11, CLDN11, in three unrelated individuals presenting with an early-onset spastic movement disorder, expressive speech disorder and eye abnormalities including hypermetropia. Brain MRI showed a myelin deficit with a discrepancy between T1-weighted and T2-weighted images and some progress in myelination especially involving the central and peripheral white matter. Exome sequencing identified heterozygous stop-loss variants c.622T>C, p.(*208Glnext*39) in two individuals and c.622T>G, p.(*208Gluext*39) in one individual, all occurring de novo. At the RNA level, the variant c.622T>C did not lead to a loss of expression in fibroblasts, indicating this transcript is not subject to nonsense-mediated decay and most likely translated into an extended protein. Extended claudin-11 is predicted to form an alpha helix not incorporated into the cytoplasmic membrane, possibly perturbing its interaction with intracellular proteins. Our observations suggest that stop-loss variants in CLDN11 expand the genetically heterogeneous spectrum of hypomyelinating leukodystrophies.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33164571

RESUMO

Background - Brugada syndrome (BrS) is characterized by the type 1 Brugada ECG pattern. Pathogenic rare variants in SCN5A (mutations) are identified in 20% of BrS families in whom incomplete penetrance and genotype-negative phenotype-positive individuals are observed. E1784K-SCN5A is the most common SCN5A mutation identified. We determined the association of a BrS genetic risk score (BrS-GRS) and SCN5A mutation type on BrS phenotype in BrS families with SCN5A mutations. Methods - Subjects with a spontaneous type 1 pattern or positive/negative drug challenge from cohorts harboring SCN5A mutations were recruited from 16 centers (n=312). Single nucleotide polymorphisms (SNP) previously associated with BrS at genome-wide significance were studied in both cohorts: rs11708996, rs10428132 and rs9388451. An additive linear genetic model for the BrS-GRS was assumed (6 SNP risk alleles). Results - In the total population (n=312), BrS-GRS ≥4 risk alleles yielded an odds ratio (OR) of 4.15 for BrS phenotype (95%CI:1.45-11.85, p=0.0078). Amongst SCN5A-positive individuals (n=258), BrS-GRS ≥4 risk alleles yielded an odds ratio (OR) of 2.35 (95%CI:0.89-6.22, p=0.0846). In SCN5A-negative relatives (n=54), BrS-GRS ≥4 alleles yielded and OR of 22.29 (95%CI:1.84-269.30, p=0.0146). Among E1784K-SCN5A positive family members (n=79), hosting ≥4 risk alleles gave an OR=5.12 (95%CI:1.93-13.62, p=0.0011). Conclusions - Common genetic variation is associated with variable expressivity of BrS phenotype in SCN5A families, explaining in part incomplete penetrance and genotype-negative phenotype-positive individuals. SCN5A mutation genotype and a BrS-GRS associate with BrS phenotype but the strength of association varies according to presence of a SCN5A mutation and severity of loss of function.

10.
J Clin Invest ; 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33201861

RESUMO

Genetic factors undoubtedly affect the development of congenital heart disease (CHD), but still remain ill-defined. We sought to identify genetic risk factors associated with CHD and to accomplish functional analysis of single nucleotide polymorphisms (SNP)-carrying genes. We performed a genome-wide association study of 4,034 Caucasian CHD patients and 8,486 healthy controls. One SNP on chromosome 5q22.2 reached genome-wide significance across all CHD phenotypes and was also indicative for septal defects. One region on chromosome 20p12.1 pointing to the MACROD2 locus identified four highly significant SNPs in patients with transposition of the great arteries (TGA). Three highly significant risk variants on chromosome 17q21.32 within the GOSR2 locus were detected in patients with anomalies of thoracic arteries and veins (ATAV). Genetic variants associated with ATAV are suggested to influence expression of WNT3, and variant rs870142 related to septal defects is proposed to influence expression of MSX1. The expression of all four genes was analyzed during cardiac differentiation of human and murine induced pluripotent stem cells in vitro and by single-cell RNAseq analyses of developing murine and human hearts. Our data show that MACROD2, GOSR2, WNT3 and MSX1 play an essential functional role in heart development at the embryonic and newborn stage.

11.
Neurol Genet ; 6(6): e525, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33134520

RESUMO

Objective: To expand the genetic spectrum of hereditary spastic paraparesis by a treatable condition and to evaluate the therapeutic effects of biotin supplementation in an adult patient with biotinidase deficiency (BD). Methods: We performed exome sequencing (ES) in a patient with the clinical diagnosis of complex hereditary spastic paraparesis. The patient was examined neurologically, including functional rating scales. We performed ophthalmologic examinations and metabolic testing. Results: A 41-year-old patient presented with slowly progressive lower limb spasticity combined with optic atrophy. He was clinically diagnosed with complex hereditary spastic paraparesis. The initial panel diagnostics did not reveal the disease-causing variant; therefore, ES was performed. ES revealed biallelic pathogenic variants in the BTD gene leading to the genetic diagnosis of BD. BD is an autosomal recessive metabolic disorder causing a broad spectrum of neurologic symptoms, optic atrophy, and dermatologic abnormalities. When treatment is initiated in time, symptoms can be prevented or reversed by biotin supplementation. After diagnosis in our patient, biotin supplementation was started. One year after the onset of therapy, symptoms remained stable with slight improvement of sensory deficits. Conclusions: These findings expand the genetic spectrum of the clinical diagnosis of complex hereditary spastic paraparesis by a treatable disease. Today, most children with BD should have been identified via newborn screening to start biotin supplementation before the onset of symptoms. However, adult patients and those born in countries without newborn screening programs for BD are at risk of being missed. Therapeutic success depends on early diagnosis and presymptomatic treatment.

12.
Arch Gynecol Obstet ; 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33245408

RESUMO

PURPOSE: TP53germline (g) mutations, associated with the Li-Fraumeni syndrome (LFS), have rarely been reported in the context of hereditary breast and ovarian cancer (HBOC). The prevalence and cancer risks in this target group are unknown and counseling remains challenging. Notably an extensive high-risk surveillance program is implemented, which evokes substantial psychological discomfort. Emphasizing the lack of consensus about clinical implications, we aim to further characterize TP53g mutations in HBOC families. METHODS: Next-generation sequencing was conducted on 1876 breast cancer (BC) patients who fulfilled the inclusion criteria for HBOC. RESULTS: (Likely) pathogenic variants in TP53 gene were present in 0.6% of the BC cohort with higher occurrence in early onset BC < 36 years. (1.1%) and bilateral vs. unilateral BC (1.1% vs. 0.3%). Two out of eleven patients with a (likely) pathogenic TP53g variant (c.542G > A; c.375G > A) did not comply with classic LFS/Chompret criteria. Albeit located in the DNA-binding domain of the p53-protein and therefore revealing no difference to LFS-related variants, they only displayed a medium transactivity reduction constituting a retainment of wildtype-like anti-proliferative functionality. CONCLUSION: Among our cohort of HBOC families, we were able to describe a clinical subgroup, which is distinct from the classic LFS-families. Strikingly, two families did not adhere to the LFS criteria, and functional analysis revealed a reduced impact on TP53 activity, which may suit to the attenuated phenotype. This is an approach that could be useful in developing individualized screening efforts for TP53g mutation carrier in HBOC families. Due to the low incidence, national/international cooperation is necessary to further explore clinical implications. This might allow providing directions for clinical recommendations in the future.

13.
Br J Pharmacol ; 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33247945

RESUMO

BACKGROUND AND PURPOSE: Heart failure (HF) is associated with an impaired NO-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway, and its augmentation is thought to be beneficial in HF therapy. We hypothesized that stimulation of sGC by the sGC stimulator riociguat (Rio) prevents pathological cardiac remodelling and HF in response to chronic pressure overload. EXPERIMENTAL APPROACH: Transverse aortic constriction (TAC) or sham surgery was performed in C57BL/6N mice. After 3 weeks of TAC when HF was established, animals were randomized to receive either riociguat (Rio) or its solvent (Sol) for 5 additional weeks. Cardiac function was evaluated weekly by echocardiography. Eight weeks after surgery, histological analyses were performed to evaluate remodelling and the transcriptome of the left ventricles (LV) was analysed by RNA Sequencing. Cell culture experiments were used for mechanistically studies. KEY RESULTS: TAC resulted in a continuous decrease of LV ejection fraction (LVEF from 56.6±2.2 to 32.0±4.1%) and an increase in LV mass (LVM/BW from 3.7±0.2 to 6.1±0.3 mg/g) until week 3. Five weeks of riociguat treatment resulted in an improved LVEF (TAC+Rio 43.4±6.0% vs. TAC+Sol 20.9±4.3%; p<0.001) and a decrease in LVM/BW (5.5±0.4 mg/g vs.7.7±0.7 mg/g; p<0.001), myocardial fibrosis and myocyte cross-sectional area. RNA sequencing revealed that riociguat reduced the expression of myocardial stress and remodelling genes (e.g. Nppa, Nppb, Myh7, collagen) and attenuated the activation of biological pathways associated with cardiac hypertrophy and HF. Riociguat reversed pathological stress response in cultivated myocytes and fibroblasts. CONCLUSION AND IMPLICATION: Stimulation of the sGC reverses TAC-induced HF and remodelling, which is associated with improved myocardial gene expression.

15.
Eur J Hum Genet ; 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887937

RESUMO

In about 30% of infantile, juvenile, or adolescent patients with steroid-resistant nephrotic syndrome (SRNS), a monogenic cause can be identified. The histological finding in SRNS is often focal segmental glomerulosclerosis (FSGS). Genetic data on adult patients are scarce with low diagnostic yields. Exome sequencing (ES) was performed in patients with adult disease onset and a high likelihood for hereditary FSGS. A high likelihood was defined if at least one of the following criteria was present: absence of a secondary cause, ≤25 years of age at initial manifestation, kidney biopsy with suspicion of a hereditary cause, extrarenal manifestations, and/or positive familial history/reported consanguinity. Patients were excluded if age at disease onset was <18 years. In 7/24 index patients with adult disease onset, a disease-causing variant could be identified by ES leading to a diagnostic yield of 29%. Eight different variants were identified in six known genes associated with monogenic kidney diseases. Six of these variants had been described before as disease-causing. In patients with a disease-causing variant, the median age at disease onset and end-stage renal disease was 26 and 38 years, respectively. The overall median time to a definite genetic diagnosis was 9 years. In 29% of patients with adult disease onset and suspected hereditary FSGS, a monogenic cause could be identified. The long delay up to the definite genetic diagnosis highlights the importance of obtaining an early genetic diagnosis to allow for personalized treatment options including weaning of immunosuppressive treatment, avoidance of repeated renal biopsy, and provision of accurate genetic counseling.

16.
PLoS One ; 15(9): e0237792, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881892

RESUMO

BACKGROUND: Ewing sarcoma (EwS) is a rare, aggressive solid tumor of childhood, adolescence and young adulthood associated with pathognomonic EWSR1-ETS fusion oncoproteins altering transcriptional regulation. Genome-wide association studies (GWAS) have identified 6 common germline susceptibility loci but have not investigated low-frequency inherited variants with minor allele frequencies below 5% due to limited genotyped cases of this rare tumor. METHODS: We investigated the contribution of rare and low-frequency variation to EwS susceptibility in the largest EwS genome-wide association study to date (733 EwS cases and 1,346 unaffected controls of European ancestry). RESULTS: We identified two low-frequency variants, rs112837127 and rs2296730, on chromosome 20 that were associated with EwS risk (OR = 0.186 and 2.038, respectively; P-value < 5×10-8) and located near previously reported common susceptibility loci. After adjusting for the most associated common variant at the locus, only rs112837127 remained a statistically significant independent signal (OR = 0.200, P-value = 5.84×10-8). CONCLUSIONS: These findings suggest rare variation residing on common haplotypes are important contributors to EwS risk. IMPACT: Motivate future targeted sequencing studies for a comprehensive evaluation of low-frequency and rare variation around common EwS susceptibility loci.


Assuntos
Loci Gênicos , Predisposição Genética para Doença , Variação Genética , Células Germinativas/metabolismo , Sarcoma de Ewing/genética , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação/genética , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética
18.
Heart Rhythm ; 17(12): 2145-2153, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32619740

RESUMO

BACKGROUND: Mutations in SCN5A are rarely found in Thai patients with Brugada syndrome (BrS). Recent evidence suggested that common genetic variations may underlie BrS in a complex inheritance model. OBJECTIVE: The purpose of this study was to find common and rare/low-frequency genetic variants predisposing to BrS in persons in Thailand. METHODS: We conducted a genome-wide association study (GWAS) to explore the association of common variants in 154 Thai BrS cases and 432 controls. We sequenced SCN5A in 131 cases and 205 controls. Variants were classified according to current guidelines, and case-control association testing was performed for rare and low-frequency variants. RESULTS: Two loci were significantly associated with BrS. The first was near SCN5A/SCN10A (lead marker rs10428132; odds ratio [OR] 2.4; P = 3 × 10-10). Conditional analysis identified a novel independent signal in the same locus (rs6767797; OR 2.3; P = 2.7 × 10-10). The second locus was near HEY2 (lead marker rs3734634; OR 2.5; P = 7 × 10-9). Rare (minor allele frequency [MAF] <0.0001) coding variants in SCN5A were found in 8 of the 131 cases (6.1% in cases vs 2.0% in controls; P = .046; OR 3.3; 95% confident interval [CI] 1.0-11.1), but an enrichment of low-frequency (MAF<0.001 and >0.0001) variants also was observed in cases, with 1 variant (SCN5A: p.Arg965Cys) detected in 4.6% of Thai BrS patients vs 0.5% in controls (P = 0.015; OR 9.8; 95% CI 1.2-82.3). CONCLUSION: The genetic basis of BrS in Thailand includes a wide spectrum of variant frequencies and effect sizes. As previously shown in European and Japanese populations, common variants near SCN5A and HEY2 are associated with BrS in the Thai population, confirming the transethnic transferability of these 2 major BrS loci.

19.
Am J Hum Genet ; 107(2): 364-373, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32707086

RESUMO

We report bi-allelic pathogenic HPDL variants as a cause of a progressive, pediatric-onset spastic movement disorder with variable clinical presentation. The single-exon gene HPDL encodes a protein of unknown function with sequence similarity to 4-hydroxyphenylpyruvate dioxygenase. Exome sequencing studies in 13 families revealed bi-allelic HPDL variants in each of the 17 individuals affected with this clinically heterogeneous autosomal-recessive neurological disorder. HPDL levels were significantly reduced in fibroblast cell lines derived from more severely affected individuals, indicating the identified HPDL variants resulted in the loss of HPDL protein. Clinical presentation ranged from severe, neonatal-onset neurodevelopmental delay with neuroimaging findings resembling mitochondrial encephalopathy to milder manifestation of adolescent-onset, isolated hereditary spastic paraplegia. All affected individuals developed spasticity predominantly of the lower limbs over the course of the disease. We demonstrated through bioinformatic and cellular studies that HPDL has a mitochondrial localization signal and consequently localizes to mitochondria suggesting a putative role in mitochondrial metabolism. Taken together, these genetic, bioinformatic, and functional studies demonstrate HPDL is a mitochondrial protein, the loss of which causes a clinically variable form of pediatric-onset spastic movement disorder.


Assuntos
Encefalopatias/genética , Proteínas Mitocondriais/genética , Doenças Neurodegenerativas/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Adulto , Alelos , Sequência de Aminoácidos , Criança , Feminino , Humanos , Masculino , Mitocôndrias/genética , Linhagem , Fenótipo , Adulto Jovem
20.
PLoS One ; 15(4): e0232073, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343731

RESUMO

Lipoprotein(a) [Lp(a)] is a major cardiovascular risk factor, which is largely genetically determined by one major gene locus, the LPA gene. Many aspects of the transcriptional regulation of LPA are poorly understood and the role of epigenetics has not been addressed yet. Therefore, we conducted an epigenome-wide analysis of DNA methylation on Lp(a) levels in two population-based studies (total n = 2208). We identified a CpG site in the LPA promoter which was significantly associated with Lp(a) concentrations. Surprisingly, the identified CpG site was found to overlap the SNP rs76735376. We genotyped this SNP de-novo in three studies (total n = 7512). The minor allele of rs76735376 (1.1% minor allele frequency) was associated with increased Lp(a) values (p = 1.01e-59) and explained 3.5% of the variation of Lp(a). Statistical mediation analysis showed that the effect on Lp(a) is rather originating from the base change itself and is not mediated by DNA methylation levels. This finding is supported by eQTL data from 208 liver tissue samples from the GTEx project, which shows a significant association of the rs76735376 minor allele with increased LPA expression. To evaluate, whether the association signal at rs76735376 may actually be derived from a stronger eQTL signal in LD with this SNP, eQTL association results of all correlated SNPs (r2≥0.1) were integrated with genetic association results. This analysis pinpointed to rs10455872 as the potential trigger of the effect of rs76735376. Furthermore, both SNPs coincide with short apo(a) isoforms. Adjusting for both, rs10455872 and the apo(a) isoforms diminished the effect size of rs76735376 to 5.38 mg/dL (p = 0.0463). This indicates that the effect of rs76735376 can be explained by both an independent effect of the SNP and a strong correlation with rs10455872 and apo(a) isoforms.


Assuntos
Metilação de DNA , Estudo de Associação Genômica Ampla/métodos , Lipoproteína(a)/genética , Lipoproteína(a)/metabolismo , Fígado/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ilhas de CpG , Epigênese Genética , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Locos de Características Quantitativas , Sequenciamento Completo do Genoma
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...