scholarly journals Genetic basis of hypercholesterolemia in adults

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Seyedmohammad Saadatagah ◽  
Merin Jose ◽  
Ozan Dikilitas ◽  
Lubna Alhabi ◽  
Alexandra A. Miller ◽  
...  
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Population Based ◽  
Single Nucleotide Variants ◽  
Genetic Etiology ◽  
Single Nucleotide ◽  
Primary Hypercholesterolemia ◽  
Clinical Criteria ◽  
Lipid Clinic ◽  
Pathogenic Variants

AbstractWe investigated monogenic and polygenic causes of hypercholesterolemia in a population-based cohort, excluding secondary hypercholesterolemia, and using an established framework to identify pathogenic variants. We studied 1682 individuals (50.2 ± 8.6 years, 41.3% males) from southeast Minnesota with primary hypercholesterolemia (low-density lipoprotein cholesterol (LDL-C) ≥155 mg/dl in the absence of identifiable secondary causes). Familial hypercholesterolemia (FH) phenotype was defined as a Dutch Lipid Clinic Network (DLCN) score ≥6. Participants underwent sequencing of LDLR, APOB, and PCSK9, and genotyping of 12 LDL-C-associated single-nucleotide variants to construct a polygenic score (PGS) for LDL-C. The presence of a pathogenic/likely pathogenic variant was considered monogenic etiology and a PGS ≥90th percentile was considered polygenic etiology. The mean LDL-C level was 187.3 ± 32.3 mg/dl and phenotypic FH was present in 8.4% of the cohort. An identifiable genetic etiology was present in 17.1% individuals (monogenic in 1.5% and polygenic in 15.6%). Phenotypic and genetic FH showed poor overlap. Only 26% of those who met the clinical criteria of FH had an identifiable genetic etiology and of those with an identifiable genetic etiology only 12.9% met clinical criteria for FH. Genetic factors explained 7.4% of the variance in LDL-C. In conclusion, in adults with primary hypercholesterolemia, 17.1% had an identifiable genetic etiology and the overlap between phenotypic and genetic FH was modest.

scholarly journals Familial hypercholesterolemia: a single-nucleotide variant (SNV) in mosaic at the Low density lipoprotein receptor (LDLR)

2018 ◽  
Author(s):  
Sonia Rodríguez-Nóvoa ◽  
Concepción Alonso ◽  
Carmen Rodríguez-Jiménez ◽  
Lara Rodriguez-Laguna ◽  
Gema Gordo ◽  
...  
Keyword(s):  
Familial Hypercholesterolemia ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Single Nucleotide Variant ◽  
Genetic Condition ◽  
Single Nucleotide ◽  
Pathogenic Variants ◽  
First Case ◽  
Density Lipoprotein Receptor

AbstractIntroductionFamilial hypercholesterolemia (FH) is most frequently caused by genetic variants in the LDLR gene. Most of LDLR pathogenic variants are missense, followed by splicing and deletion/insertions variants. Mosaicism is a genetic condition in which an individual shows more than one clone of cells with different genotypes.ObjectiveMolecular characterization of a patient with hypercholesterolemia.MethodsGenetic analysis of DNA from peripheral blood and saliva was performed by NGS, sanger sequencing and pyrosequencing technologies.ResultsNGS analysis detected the pathogenic variant LDLR:c.1951G>T:p.(Asp651Tyr) in 9%-12% of reads. The presence of the variant was confirmed by pyrosequencing analysis.ConclusionHerein, we report the first case of a mosaic single nucleotide variant affecting the LDLR gene in a patient with familial hypercholesterolemia. As has been described for other pathologies, mosaicism could be underestimated in FH and its detection will improve with the introduction of NGS technologies in the diagnostic routine.

3259Next-generation sequencing to confirm clinical FH in The Netherlands

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Reeskamp ◽  
L C Zuurbier ◽  
G K Hovingh ◽  
J C Defesche
Keyword(s):  
The Netherlands ◽  
Low Density Lipoprotein ◽  
Genetic Defect ◽  
Copy Number Variants ◽  
Density Lipoprotein ◽  
Molecular Testing ◽  
Targeted Next Generation Sequencing ◽  
Lipid Clinic ◽  
Pathogenic Variants ◽  
Generation Sequencing

Abstract Background Pathogenic variants in the genes encoding the low-density lipoprotein receptor (LDLR), apolipoprotein B100 (APOB) and proprotein convertase subtilisin/kexin type 9 (PCSK9)) are known to cause familial hypercholesterolemia (FH), a disease characterized by high LDL-C levels. We set out to investigate which proportion of patients with extremely elevated LDL-C levels, who were referred for molecular analysis, carry a mutation in any of the three FH genes or other, putative FH genes. Methods Targeted next-generation sequencing of 28 genes involved in lipid metabolism was performed in 1475 clinical FH patients with LDL-C levels >5mmol/L (corresponding with possible, probable and definite FH score according to the Dutch Lipid Clinic Network criteria) and triglyceride levels <4.5 mmol/L. Genetic variants and copy number variants were curated consecutively using specialist analysis software. (Likely) pathogenic variants in LDLR, APOB, or PCSK9 were annotated as FH-causing variants. Results 14.3% of the 1475 patients with clinical FH were heterozygous carriers of a mutation in LDLR, APOB, or PCSK9. This number ranged from 8% in the lowest LDL-C group (5–5.99 mmol/L) to 56% in patients with the highest LDL-C levels (>8 mmol/L). Patients with LDLR, APOB, or PCSK9 variants had median LDL-C levels of 6.8 [5.7–7.9], 6.2 [5.1–7.0], and 6.4 [5.7–6.8] mmol/L [interquartile range], respectively. Mutation-negative FH patients had median LDL-C levels of 5.8 [5.2–6.5] mmol/L. Of the FH mutation-negative patients 7.4% had a (likely) pathogenic variant in the gene encoding lipoprotein lipase (LPL) and 1.3% in the apolipoprotein E (APOE) gene. The proportion of FH mutation-negative patients carrying an APOE variant increased from 1.2% in the lowest LDL-C group to 7.5% in patients with LDL-C >8 mmol/L. Mutation-positive FH patients were significantly younger (41.61±17.53 years vs 52.62±13.28 years P<0.001) and had a significant lower BMI (25.86±4.87 vs 26.55±4.07kg/m2, P=0.02) compared to mutation negative patients. Figure 1 Conclusions A genetic defect in LDLR, APOB or PCSK9 is identified in only 14.3% of the patients with a clinical FH phenotype (defined as LDL-C >5 mmol/L) referred for molecular testing in the Netherlands. Mutations in LPL and APOE were found in a minor proportion of the FH mutation-negative patients. Our finding that a mutation is only found 56% of patients who present with LDL-C levels above 8 mmol/L indicates that either misclassification of FH and/or other genetic defects may be present in this group. Acknowledgement/Funding Grant [016.156.445] from The Netherlands Organisation for Scientific Research (NWO)

scholarly journals Effects of Weight Gain after 20 Years of Age and Incidence of Hyper-Low-Density Lipoprotein Cholesterolemia: The Iki Epidemiological Study of Atherosclerosis and Chronic Kidney Disease (ISSA-CKD)

2021 ◽  
Vol 10 (14) ◽  
pp. 3098
Author(s):  
Shota Okutsu ◽  
Yoshifumi Kato ◽  
Shunsuke Funakoshi ◽  
Toshiki Maeda ◽  
Chikara Yoshimura ◽  
...  
Keyword(s):  
Weight Gain ◽  
General Population ◽  
Ldl Cholesterol ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Population Based ◽  
Lipid Lowering ◽  
Low Density ◽  
Obesity Hypertension ◽  
Old Men

The aim of this study was to investigate the effects of long-term weight gain from the age of 20 on incidence of hyper-low-density-lipoprotein (LDL) cholesterolemia in the general population of Japanese people. Methods: We conducted a population-based retrospective cohort study using annual health checkup data for residents of Iki City, Nagasaki Prefecture, Japan. A total of 3179 adult (≥30 years old) men and women without hyper-LDL cholesterolemia at baseline, who underwent two or more health checkups were included in the analysis. Information on weight gain (≥10 kg) after 20 years of age was obtained using questionnaire. The outcome of this study was development of hyper-LDL cholesterolemia defined as LDL-cholesterol level ≥3.62 mmol/L and/or initiation of lipid-lowering medications. Results: During a mean follow-up period of 4.53 years, 665 of the 3179 participants developed hyper-LDL cholesterolemia (46.5/1000 person-years). The incidence of hyper-LDL cholesterolemia was higher in participants with a weight gain of ≥10 kg (55.3/1000 person-years) than among those with a weight gain of <10 kg (41.8/1000 person-years). This association remained statistically significant even after adjustment for age, sex, smoking, daily drinking, exercise, obesity, hypertension, and diabetes (multivariable hazard ratio 1.31, 95% confidence interval 1.08–1.58, p = 0.006). Conclusion: A weight gain of ≥10 after 20 years of age affected the development of hyper-LDL cholesterol regardless of age, sex, and obesity in a general population of Japanese.

scholarly journals Unsuspected somatic mosaicism for FBN1 gene contributes to Marfan syndrome

2021 ◽  
Author(s):  
Pauline Arnaud ◽  
Hélène Morel ◽  
Olivier Milleron ◽  
Laurent Gouya ◽  
Christine Francannet ◽  
...  
Keyword(s):  
Marfan Syndrome ◽  
Somatic Mosaicism ◽  
Variant Calling ◽  
Copy Number Variations ◽  
Pathogenic Variant ◽  
Single Nucleotide Variants ◽  
Bioinformatics Analyses ◽  
Single Nucleotide ◽  
Fbn1 Gene ◽  
Pathogenic Variants

Abstract Purpose Individuals with mosaic pathogenic variants in the FBN1 gene are mainly described in the course of familial screening. In the literature, almost all these mosaic individuals are asymptomatic. In this study, we report the experience of our team on more than 5,000 Marfan syndrome (MFS) probands. Methods Next-generation sequencing (NGS) capture technology allowed us to identify five cases of MFS probands who harbored a mosaic pathogenic variant in the FBN1 gene. Results These five sporadic mosaic probands displayed classical features usually seen in Marfan syndrome. Combined with the results of the literature, these rare findings concerned both single-nucleotide variants and copy-number variations. Conclusion This underestimated finding should not be overlooked in the molecular diagnosis of MFS patients and warrants an adaptation of the parameters used in bioinformatics analyses. The five present cases of symptomatic MFS probands harboring a mosaic FBN1 pathogenic variant reinforce the fact that apparently asymptomatic mosaic parents should have a complete clinical examination and a regular cardiovascular follow-up. We advise that individuals with a typical MFS for whom no single-nucleotide pathogenic variant or exon deletion/duplication was identified should be tested by NGS capture panel with an adapted variant calling analysis.

scholarly journals Improving Familial Hypercholesterolemia Index Case Detection: Sequential Active Screening from Centralized Analytical Data

2021 ◽  
Vol 10 (4) ◽  
pp. 749
Author(s):  
Fernando Sabatel-Pérez ◽  
Joaquín Sánchez-Prieto ◽  
Víctor Manuel Becerra-Muñoz ◽  
Juan Horacio Alonso-Briales ◽  
Pedro Mata ◽  
...  
Keyword(s):  
Familial Hypercholesterolemia ◽  
Diagnostic Yield ◽  
Low Density Lipoprotein ◽  
Analytical Data ◽  
Genetic Diagnosis ◽  
Density Lipoprotein ◽  
Screening Strategy ◽  
Cascade Screening ◽  
Active Screening ◽  
Lipid Clinic

The majority of familial hypercholesterolemia index cases (FH-IC) remain underdiagnosed and undertreated because there are no well-defined strategies for the universal detection of FH. The aim of this study was to evaluate the diagnostic yield of an active screening for FH-IC based on centralized analytical data. From 2016 to 2019, a clinical screening of FH was performed on 469 subjects with severe hypercholesterolemia (low-density lipoprotein cholesterol ≥220 mg/dL), applying the Dutch Lipid Clinic Network (DLCN) criteria. All patients with a DLCN ≥ 6 were genetically tested, as were 10 patients with a DLCN of 3–5 points to compare the diagnostic yield between the two groups. FH was genetically confirmed in 57 of the 84 patients with DLCN ≥ 6, with a genetic diagnosis rate of 67.9% and an overall prevalence of 12.2% (95% confidence interval: 9.3% to 15.5%). Before inclusion in the study, only 36.8% (n = 21) of the patients with the FH mutation had been clinically diagnosed with FH; after genetic screening, FH detection increased 2.3-fold (p < 0.001). The sequential, active screening strategy for FH-IC increases the diagnostic yield for FH with a rational use of the available resources, which may facilitate the implementation of FH universal and family-based cascade screening strategies.

scholarly journals Re-evaluation of single nucleotide variants and identification of structural variants in a cohort of 45 sudden unexplained death cases

2021 ◽  
Author(s):  
Jacqueline Neubauer ◽  
Shouyu Wang ◽  
Giancarlo Russo ◽  
Cordula Haas
Keyword(s):  
Sudden Death ◽  
Cardiac Diseases ◽  
Structural Variants ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Sudden Unexplained Death ◽  
Unexplained Death ◽  
Pathogenic Variants ◽  
The Impact ◽  
Death Cases

AbstractSudden unexplained death (SUD) takes up a considerable part in overall sudden death cases, especially in adolescents and young adults. During the past decade, many channelopathy- and cardiomyopathy-associated single nucleotide variants (SNVs) have been identified in SUD studies by means of postmortem molecular autopsy, yet the number of cases that remain inconclusive is still high. Recent studies had suggested that structural variants (SVs) might play an important role in SUD, but there is no consensus on the impact of SVs on inherited cardiac diseases. In this study, we searched for potentially pathogenic SVs in 244 genes associated with cardiac diseases. Whole-exome sequencing and appropriate data analysis were performed in 45 SUD cases. Re-analysis of the exome data according to the current ACMG guidelines identified 14 pathogenic or likely pathogenic variants in 10 (22.2%) out of the 45 SUD cases, whereof 2 (4.4%) individuals had variants with likely functional effects in the channelopathy-associated genes SCN5A and TRDN and 1 (2.2%) individual in the cardiomyopathy-associated gene DTNA. In addition, 18 structural variants (SVs) were identified in 15 out of the 45 individuals. Two SVs with likely functional impairment were found in the coding regions of PDSS2 and TRPM4 in 2 SUD cases (4.4%). Both were identified as heterozygous deletions, which were confirmed by multiplex ligation-dependent probe amplification. In conclusion, our findings support that SVs could contribute to the pathology of the sudden death event in some of the cases and therefore should be investigated on a routine basis in suspected SUD cases.

Estimated Prevalence of Familial Hypercholesterolemia Among Egyptian Patients with Acute Coronary Syndromes; Analysis from The Cardiorisk Project

2021 ◽  
Vol 23 (Supplement_D) ◽  
Author(s):  
Ashraf Reda ◽  
Ahmed Bendary ◽  
Ahmed Shawky Elserafy ◽  
Elsayed Farag ◽  
Tamer Mostafa ◽  
...  
Keyword(s):  
Familial Hypercholesterolemia ◽  
Acute Coronary Syndromes ◽  
Total Population ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Cross Sectional ◽  
Lipid Clinic ◽  
Egyptian Patients ◽  
Coronary Syndromes ◽  
Premature Cad

Abstract Aims The prevalence of familial hypercholesterolemia (FH) in Egypt is largely un- known. We aimed to estimate the prevalence of FH among 3224 Egyptian patients with acute coronary syndromes enrolled from 2015 to 2018 in the nationwide cross- sectional cardioRisk project. Methods and Results We applied the Dutch Lipid Clinic criteria for the diagnosis of FH on the available data recorded for the patients enrolled in the CardioRisk project. Two main criteria were applied: the presence of premature CAD (given 2 points in the Dutch criteria), and the categorized low density lipoprotein cholesterol (LDL-C) lev- els (given 1, 3, 5, or 8 points in the Dutch criteria according to the level). From a total of 3224 patients, 2743 patients had available LDL-C levels. Among those patients, when applying the abovementioned 2 criteria, we estimated that 472 patients had at least ‘possible’ FH (17.2% of the total population). Specifically, 4 patients had ‘defi- nite’ FH (0.1%), 7 patients had ‘probable’ FH (0.25%), and 461 patients had ‘possi- ble’ FH (16.8%). Conclusion The estimated prevalence of at least ‘possible’ FH among Egyptian patients with ACS is 17%.

Abstract 14681: Comparative Study Between International Guidelines in Detecting Pediatric Familial Hypercholesterolemia Through a Unique Community Health System in Kagawa, Japan

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Keiji Matsunaga ◽  
Asako Mizobuchi ◽  
Hayato Tada ◽  
Tsuyoshi Sasaki ◽  
Yoshihiro Asano ◽  
...  
Keyword(s):  
Health System ◽  
Community Health ◽  
Familial Hypercholesterolemia ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Hereditary Disease ◽  
International Guidelines ◽  
Number Of Children ◽  
Lipid Clinic ◽  
Lipid Screening

Introduction: Familial hypercholesterolemia (FH) is an autosomal hereditary disease found in patients who have elevated low-density lipoprotein cholesterol (LDL-C) from birth. Early detection and treatment of FH during childhood potentially reduces the risk of premature cardiovascular events. In Kagawa prefecture, a unique community health system, involving three steps, has been conducted to prevent lifestyle-related diseases for 10-year-old children. This system includes universal lipid screening, selection by pediatricians, and next-generation sequencing (NGS) of FH-related genes in hospitals. The aim of this study is to compare 3 international guidelines to detect pediatric FH with this unique community health system in Kagawa. Methods: In Kagawa prefecture, the universal lipid screening of approximately 8,000 children at 10 years of age is performed annually, covering over 90% of the target group. After excluding secondary hypercholesterolemia, pediatric clinics introduced children with LDL-C >140mg/dL to 4 designated hospitals to perform NGS. We applied the guidelines of the Dutch Lipid Clinic Network (DLCN), Simon Broome (SB), and the Japanese Atherosclerosis Society (JAS) to children who received NGS in the unique community health system in Kagawa. Results: We performed NGS for 46 children from January 2018 to February 2020 (LDL-C 186.0±50.3 mg/dL; Male/F 27/19) and 26 (57%) had FH genetic mutations (23 LDL-R and 3 PCSK9 mutations). Seventeen children met FH criteria for DLCN (35%), 10 for Simon Broome (22%), and 11 for JAS (24%), respectively. The combination of NGS and either of the 3 guidelines increased the number of children diagnosed as FH up to 31 (67%). Conclusion: International guidelines detected only half of pediatric FH who were diagnosed by the unique community health system in Kagawa. Further investigation will be required to build an effective universal screening system for pediatric FH.

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