1
|
Grejtakova D, Boronova I, Bernasovska J, Bellosta S. PCSK9 and Lipid Metabolism: Genetic Variants, Current Therapies, and Cardiovascular Outcomes. Cardiovasc Drugs Ther 2024:10.1007/s10557-024-07599-5. [PMID: 38907775 DOI: 10.1007/s10557-024-07599-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/12/2024] [Indexed: 06/24/2024]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in the modulation of lipid metabolism as a critical negative regulator of hepatic low-density lipoprotein receptor (LDLR) levels and circulating low-density lipoprotein (LDL) clearance. Numerous gain-of-function (GOF) mutations in PCSK9 have been identified as causing familial hypercholesterolemia (FH) by reducing LDLR levels, and loss-of-function (LOF) mutations associated with a hypercholesterolemia phenotype protective against atherosclerosis. PCSK9 represents an example of successful translational research resulting in the identification of PCSK9 as a major drug target for a lipid-lowering therapy. To explore the genetic constitution of PCSK9 and its biologic role, in this review, we summarize the current evidence of clinically significant PCSK9 genetic variants involved in lipid metabolism as well as emphasize the importance of PCSK9 inhibition for the improvement of cardiovascular outcomes by conducting a meta-analysis of the available data on the incidence of cardiovascular disease events.
Collapse
Affiliation(s)
- Daniela Grejtakova
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia.
| | - Iveta Boronova
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia
| | - Jarmila Bernasovska
- Laboratory of Molecular Genetics, Department of Biology, Faculty of Humanities and Natural Sciences, University of Presov, 17 November 1, Presov, 08001, Slovakia
| | - Stefano Bellosta
- Department of Pharmacological and Biomolecular Sciences "Rodolfo Paoletti", Università Degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy
| |
Collapse
|
2
|
Medeiros AM, Alves AC, Miranda B, Chora JR, Bourbon M. Unraveling the genetic background of individuals with a clinical familial hypercholesterolemia phenotype. J Lipid Res 2024; 65:100490. [PMID: 38122934 PMCID: PMC10832474 DOI: 10.1016/j.jlr.2023.100490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 12/04/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023] Open
Abstract
Familial hypercholesterolemia (FH) is a common genetic disorder of lipid metabolism caused by pathogenic/likely pathogenic variants in LDLR, APOB, and PCSK9 genes. Variants in FH-phenocopy genes (LDLRAP1, APOE, LIPA, ABCG5, and ABCG8), polygenic hypercholesterolemia, and hyperlipoprotein (a) [Lp(a)] can also mimic a clinical FH phenotype. We aim to present a new diagnostic tool to unravel the genetic background of clinical FH phenotype. Biochemical and genetic study was performed in 1,005 individuals with clinical diagnosis of FH, referred to the Portuguese FH Study. A next-generation sequencing panel, covering eight genes and eight SNPs to determine LDL-C polygenic risk score and LPA genetic score, was validated, and used in this study. FH was genetically confirmed in 417 index cases: 408 heterozygotes and 9 homozygotes. Cascade screening increased the identification to 1,000 FH individuals, including 11 homozygotes. FH-negative individuals (phenotype positive and genotype negative) have Lp(a) >50 mg/dl (30%), high polygenic risk score (16%), other monogenic lipid metabolism disorders (1%), and heterozygous pathogenic variants in FH-phenocopy genes (2%). Heterozygous variants of uncertain significance were identified in primary genes (12%) and phenocopy genes (7%). Overall, 42% of our cohort was genetically confirmed with FH. In the remaining individuals, other causes for high LDL-C were identified in 68%. Hyper-Lp(a) or polygenic hypercholesterolemia may be the cause of the clinical FH phenotype in almost half of FH-negative individuals. A small part has pathogenic variants in ABCG5/ABCG8 in heterozygosity that can cause hypercholesterolemia and should be further investigated. This extended next-generation sequencing panel identifies individuals with FH and FH-phenocopies, allowing to personalize each person's treatment according to the affected pathway.
Collapse
Affiliation(s)
- Ana Margarida Medeiros
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Ana Catarina Alves
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Beatriz Miranda
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Joana Rita Chora
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Mafalda Bourbon
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
| |
Collapse
|
3
|
Larrea-Sebal A, Jebari-Benslaiman S, Galicia-Garcia U, Jose-Urteaga AS, Uribe KB, Benito-Vicente A, Martín C. Predictive Modeling and Structure Analysis of Genetic Variants in Familial Hypercholesterolemia: Implications for Diagnosis and Protein Interaction Studies. Curr Atheroscler Rep 2023; 25:839-859. [PMID: 37847331 PMCID: PMC10618353 DOI: 10.1007/s11883-023-01154-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2023] [Indexed: 10/18/2023]
Abstract
PURPOSE OF REVIEW Familial hypercholesterolemia (FH) is a hereditary condition characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C), which increases the risk of cardiovascular disease if left untreated. This review aims to discuss the role of bioinformatics tools in evaluating the pathogenicity of missense variants associated with FH. Specifically, it highlights the use of predictive models based on protein sequence, structure, evolutionary conservation, and other relevant features in identifying genetic variants within LDLR, APOB, and PCSK9 genes that contribute to FH. RECENT FINDINGS In recent years, various bioinformatics tools have emerged as valuable resources for analyzing missense variants in FH-related genes. Tools such as REVEL, Varity, and CADD use diverse computational approaches to predict the impact of genetic variants on protein function. These tools consider factors such as sequence conservation, structural alterations, and receptor binding to aid in interpreting the pathogenicity of identified missense variants. While these predictive models offer valuable insights, the accuracy of predictions can vary, especially for proteins with unique characteristics that might not be well represented in the databases used for training. This review emphasizes the significance of utilizing bioinformatics tools for assessing the pathogenicity of FH-associated missense variants. Despite their contributions, a definitive diagnosis of a genetic variant necessitates functional validation through in vitro characterization or cascade screening. This step ensures the precise identification of FH-related variants, leading to more accurate diagnoses. Integrating genetic data with reliable bioinformatics predictions and functional validation can enhance our understanding of the genetic basis of FH, enabling improved diagnosis, risk stratification, and personalized treatment for affected individuals. The comprehensive approach outlined in this review promises to advance the management of this inherited disorder, potentially leading to better health outcomes for those affected by FH.
Collapse
Affiliation(s)
- Asier Larrea-Sebal
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
- Department of Molecular Biophysics, Biofisika Institute, University of Basque Country and Consejo Superior de Investigaciones Científicas (UPV/EHU, CSIC), 48940, Leioa, Spain
- Fundación Biofisika Bizkaia, 48940, Leioa, Spain
| | - Shifa Jebari-Benslaiman
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
- Department of Molecular Biophysics, Biofisika Institute, University of Basque Country and Consejo Superior de Investigaciones Científicas (UPV/EHU, CSIC), 48940, Leioa, Spain
| | - Unai Galicia-Garcia
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
- Department of Molecular Biophysics, Biofisika Institute, University of Basque Country and Consejo Superior de Investigaciones Científicas (UPV/EHU, CSIC), 48940, Leioa, Spain
| | - Ane San Jose-Urteaga
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
| | - Kepa B Uribe
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
| | - Asier Benito-Vicente
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
- Department of Molecular Biophysics, Biofisika Institute, University of Basque Country and Consejo Superior de Investigaciones Científicas (UPV/EHU, CSIC), 48940, Leioa, Spain
| | - César Martín
- Department of Biochemistry and Molecular Biology, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain.
- Department of Molecular Biophysics, Biofisika Institute, University of Basque Country and Consejo Superior de Investigaciones Científicas (UPV/EHU, CSIC), 48940, Leioa, Spain.
| |
Collapse
|
4
|
Hummelgaard S, Vilstrup JP, Gustafsen C, Glerup S, Weyer K. Targeting PCSK9 to tackle cardiovascular disease. Pharmacol Ther 2023; 249:108480. [PMID: 37331523 DOI: 10.1016/j.pharmthera.2023.108480] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/07/2023] [Accepted: 06/14/2023] [Indexed: 06/20/2023]
Abstract
Lowering blood cholesterol levels efficiently reduces the risk of developing atherosclerotic cardiovascular disease (ASCVD), including coronary artery disease (CAD), which is the main cause of death worldwide. CAD is caused by plaque formation, comprising cholesterol deposits in the coronary arteries. Proprotein convertase subtilisin kexin/type 9 (PCSK9) was discovered in the early 2000s and later identified as a key regulator of cholesterol metabolism. PCSK9 induces lysosomal degradation of the low-density lipoprotein (LDL) receptor in the liver, which is responsible for clearing LDL-cholesterol (LDL-C) from the circulation. Accordingly, gain-of-function PCSK9 mutations are causative of familial hypercholesterolemia, a severe condition with extremely high plasma cholesterol levels and increased ASCVD risk, whereas loss-of-function PCSK9 mutations are associated with very low LDL-C levels and protection against CAD. Since the discovery of PCSK9, extensive investigations in developing PCSK9 targeting therapies have been performed. The combined delineation of clear biology, genetic risk variants, and PCSK9 crystal structures have been major drivers in developing antagonistic molecules. Today, two antibody-based PCSK9 inhibitors have successfully progressed to clinical application and shown to be effective in reducing cholesterol levels and mitigating the risk of ASCVD events, including myocardial infarction, stroke, and death, without any major adverse effects. A third siRNA-based inhibitor has been FDA-approved but awaits cardiovascular outcome data. In this review, we outline the PCSK9 biology, focusing on the structure and nonsynonymous mutations reported in the PCSK9 gene and elaborate on PCSK9-lowering strategies under development. Finally, we discuss future perspectives with PCSK9 inhibition in other severe disorders beyond cardiovascular disease.
Collapse
Affiliation(s)
| | | | | | - Simon Glerup
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Draupnir Bio, INCUBA Skejby, Aarhus, Denmark
| | - Kathrin Weyer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
5
|
Calling and Phasing of Single-Nucleotide and Structural Variants of the LDLR Gene Using Oxford Nanopore MinION. Int J Mol Sci 2023; 24:ijms24054471. [PMID: 36901902 PMCID: PMC10003201 DOI: 10.3390/ijms24054471] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/27/2023] [Accepted: 02/22/2023] [Indexed: 03/12/2023] Open
Abstract
The LDLR locus has clinical significance for lipid metabolism, Mendelian familial hypercholesterolemia (FH), and common lipid metabolism-related diseases (coronary artery disease and Alzheimer's disease), but its intronic and structural variants are underinvestigated. The aim of this study was to design and validate a method for nearly complete sequencing of the LDLR gene using long-read Oxford Nanopore sequencing technology (ONT). Five PCR amplicons from LDLR of three patients with compound heterozygous FH were analyzed. We used standard workflows of EPI2ME Labs for variant calling. All rare missense and small deletion variants detected previously by massively parallel sequencing and Sanger sequencing were identified using ONT. One patient had a 6976 bp deletion (exons 15 and 16) that was detected by ONT with precisely located breakpoints between AluY and AluSx1. Trans-heterozygous associations between mutation c.530C>T and c.1054T>C, c.2141-966_2390-330del, and c.1327T>C, and between mutations c.1246C>T and c.940+3_940+6del of LDLR, were confirmed. We demonstrated the ability of ONT to phase variants, thereby enabling haplotype assignment for LDLR with personalized resolution. The ONT-based method was able to detect exonic variants with the additional benefit of intronic analysis in one run. This method can serve as an efficient and cost-effective tool for diagnosing FH and conducting research on extended LDLR haplotype reconstruction.
Collapse
|
6
|
Gidding SS, Wiegman A, Groselj U, Freiberger T, Peretti N, Dharmayat KI, Daccord M, Bedlington N, Sikonja J, Ray KK, Santos RD, Halle M, Tokgözoğlu L, Gutiérrez-Ibarluzea I, Pinto FJ, Geanta M. Paediatric familial hypercholesterolaemia screening in Europe: public policy background and recommendations. Eur J Prev Cardiol 2022; 29:2301-2311. [PMID: 36059237 DOI: 10.1093/eurjpc/zwac200] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/12/2022] [Accepted: 09/02/2022] [Indexed: 02/01/2023]
Abstract
Familial hypercholesterolaemia (FH) is under-recognized and under-treated in Europe leading to significantly higher risk for premature heart disease in those affected. As treatment beginning early in life is highly effective in preventing heart disease and cost-effective in these patients, screening for FH is crucial. It has therefore now been recognized by the European Commission Public Health Best Practice Portal as an effective strategy. Model programmes exist in Europe to identify young individuals with FH, which are based on cascade screening of first-degree relatives of affected individuals, universal screening for high cholesterol, opportunistic screening of high-risk individuals, or a combination of the above approaches. Recommendations presented herein to improve identification of FH emphasize that every country should have an FH screening programme. These programmes should be adapted from existing strategies to best fit the individual country's healthcare system, governments should provide financial support for these programmes and related care, and further research to optimize care and implementations should be conducted.
Collapse
Affiliation(s)
- Samuel S Gidding
- The European FH Patient Network (FH Europe), Star House, Star Hill, Rochester, Kent ME1 1UX, UK
| | - Albert Wiegman
- Department of Paediatrics, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Urh Groselj
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Bohoričeva ulica 20, Ljubljana, Slovenia
| | - Tomas Freiberger
- Centre for Cardiovascular Surgery and Transplantation, Pekařská 53, 656 91 Brno, Czech Republic.,Medical Faculty, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Noel Peretti
- Department of Pediatric Gastroenterology-Hepatology and Nutrition, Hospices Civil de Lyon HCL, Hôpital Femme Mere Enfant HFME, Bron, France.,Univ-Lyon, CarMeN Laboratory, INSERM U1060, INRAE U1397, Université Claude Bernard Lyon-1, Oullins, Lyon, France
| | - Kanika I Dharmayat
- Imperial Centre for Cardiovascular Disease Prevention, Department of Primary Care and Public Health, Imperial College London, St Dunstan's Road, London W6 8RP, UK
| | - Magdalena Daccord
- The European FH Patient Network (FH Europe), Star House, Star Hill, Rochester, Kent ME1 1UX, UK
| | - Nicola Bedlington
- The European FH Patient Network (FH Europe), Star House, Star Hill, Rochester, Kent ME1 1UX, UK
| | - Jaka Sikonja
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Bohoričeva ulica 20, Ljubljana, Slovenia
| | - Kausik K Ray
- Imperial Centre for Cardiovascular Disease Prevention, Department of Primary Care and Public Health, Imperial College London, St Dunstan's Road, London W6 8RP, UK
| | - Raul D Santos
- Heart Institute (InCor), University of Sao Paulo Medical School Hospital, Sao Paulo, Brazil.,Preventive Medicine Centre and Cardiology Program, Hospital Israelita Albert Einstein, Sao Paulo, Brazil.,International Atherosclerosis Society (IAS), Milan, Italy
| | - Martin Halle
- Department of Prevention and Sports Medicine, Faculty of Medicine, University Hospital 'Klinikum rechts der Isar', Technical University Munich, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung), partner site Munich, Munich Heart Alliance, Munich, Germany
| | - Lale Tokgözoğlu
- Department of Cardiology, Hacettepe University, Ankara, Turkey
| | - Iñaki Gutiérrez-Ibarluzea
- Head of Knowledge Management and Health Technology Assessment, Basque Foundation for Health Innovation and Research (BIOEF), Ronda de Azkue, 1, 48902 Barakaldo (Bizkaia), Basque Country, Spain
| | - Fausto J Pinto
- World Heart Federation, Geneva, Switzerland.,Cardiovascular Department, CCUL, CAML, Lisbon School of Medicine, University of Lisbon, Portugal
| | - Marius Geanta
- The European FH Patient Network (FH Europe), Star House, Star Hill, Rochester, Kent ME1 1UX, UK
| |
Collapse
|
7
|
Genetic Spectrum of Familial Hypercholesterolaemia in the Malaysian Community: Identification of Pathogenic Gene Variants Using Targeted Next-Generation Sequencing. Int J Mol Sci 2022; 23:ijms232314971. [PMID: 36499307 PMCID: PMC9736953 DOI: 10.3390/ijms232314971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/11/2022] [Accepted: 11/17/2022] [Indexed: 12/02/2022] Open
Abstract
Familial hypercholesterolaemia (FH) is caused by mutations in lipid metabolism genes, predominantly in low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin-type 9 (PCSK9) and LDL receptor adaptor protein 1 (LDLRAP1). The prevalence of genetically confirmed FH and the detection rate of pathogenic variants (PV) amongst clinically diagnosed patients is not well established. Targeted next-generation sequencing of LDLR, APOB, PCSK9 and LDLRAP1 was performed on 372 clinically diagnosed Malaysian FH subjects. Out of 361 variants identified, 40 of them were PV (18 = LDLR, 15 = APOB, 5 = PCSK9 and 2 = LDLRAP1). The majority of the PV were LDLR and APOB, where the frequency of both PV were almost similar. About 39% of clinically diagnosed FH have PV in PCSK9 alone and two novel variants of PCSK9 were identified in this study, which have not been described in Malaysia and globally. The prevalence of genetically confirmed potential FH in the community was 1:427, with a detection rate of PV at 0.2% (12/5130). About one-fourth of clinically diagnosed FH in the Malaysian community can be genetically confirmed. The detection rate of genetic confirmation is similar between potential and possible FH groups, suggesting a need for genetic confirmation in index cases from both groups. Clinical and genetic confirmation of FH index cases in the community may enhance the early detection of affected family members through family cascade screening.
Collapse
|
8
|
Graça R, Alves AC, Zimon M, Pepperkok R, Bourbon M. Functional profiling of LDLR variants: important evidence for variant classification. J Clin Lipidol 2022; 16:516-524. [DOI: 10.1016/j.jacl.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/20/2022] [Accepted: 04/25/2022] [Indexed: 10/18/2022]
|
9
|
Establishing the Mutational Spectrum of Hungarian Patients with Familial Hypercholesterolemia. Genes (Basel) 2022; 13:genes13010153. [PMID: 35052492 PMCID: PMC8775528 DOI: 10.3390/genes13010153] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 02/05/2023] Open
Abstract
Familial hypercholesterolemia (FH) is one of the most common autosomal, dominantly inherited diseases affecting cholesterol metabolism, which, in the absence of treatment, leads to the development of cardiovascular complications. The disease is still underdiagnosed, even though an early diagnosis would be of great importance for the patient to receive proper treatment and to prevent further complications. No studies are available describing the genetic background of Hungarian FH patients. In this work, we present the clinical and molecular data of 44 unrelated individuals with suspected FH. Sequencing of five FH-causing genes (LDLR, APOB, PCSK9, LDLRAP1 and STAP1) has been performed by next-generation sequencing (NGS). In cases where a copy number variation (CNV) has been detected by NGS, confirmation by multiplex ligation-dependent probe amplification (MLPA) has also been performed. We identified 47 causal or potentially causal (including variants of uncertain significance) LDLR and APOB variants in 44 index patients. The most common variant in the APOB gene was the c.10580G>A p.(Arg3527Gln) missense alteration, this being in accordance with literature data. Several missense variants in the LDLR gene were detected in more than one index patient. LDLR variants in the Hungarian population largely overlap with variants detected in neighboring countries.
Collapse
|
10
|
Hu H, Shu T, Ma J, Chen R, Wang J, Wang S, Lin S, Chen X. Two Novel Disease-Causing Mutations in the LDLR of Familial Hypercholesterolemia. Front Genet 2022; 12:762587. [PMID: 34970301 PMCID: PMC8712701 DOI: 10.3389/fgene.2021.762587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 11/10/2021] [Indexed: 12/03/2022] Open
Abstract
As an autosomal dominant disorder, familial hypercholesterolemia (FH) is mainly caused by pathogenic mutations in lipid metabolism-related genes. The aim of this study is to investigate the genetic mutations in FH patients and verify their pathogenicity. First of all, a pedigree investigation was conducted in one family diagnosed with FH using the Dutch Lipid Clinic Network criteria. The high-throughput sequencing was performed on three family members to explore genetic mutations. The effects of low-density lipoprotein receptor (LDLR) variants on their expression levels and activity were further validated by silico analysis and functional studies. The results revealed that LDLC levels of the proband and his daughter were abnormally elevated. The whole-exome sequencing and Sanger sequencing were used to confirm that there were two LDLR missense mutations (LDLR c.226 G > C, c.1003 G > T) in this family. Bioinformatic analysis (Mutationtaster) indicated that these two mutations might be disease-causing variants. In vitro experiments suggested that LDLR c.226 G > C and c.1003 G > T could attenuate the uptake of Dil-LDL by LDLR. In conclusion, the LDLR c.226 G > C and c.1003 G > T variants might be pathogenic for FH by causing uptake dysfunction of the LDLR.
Collapse
Affiliation(s)
- Haochang Hu
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| | - Tian Shu
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| | - Jun Ma
- Department of Medical Ultrasonics, First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Ruoyu Chen
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| | - Jian Wang
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| | | | - Shaoyi Lin
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| | - Xiaomin Chen
- Department of Cardiology, Ningbo First Hospital, Ningbo, China
| |
Collapse
|
11
|
Izar MCDO, Giraldez VZR, Bertolami A, Santos Filho RDD, Lottenberg AM, Assad MHV, Saraiva JFK, Chacra APM, Martinez TLR, Bahia LR, Fonseca FAH, Faludi AA, Sposito AC, Chagas ACP, Jannes CE, Amaral CK, Araújo DBD, Cintra DE, Coutinho EDR, Cesena F, Xavier HT, Mota ICP, Giuliano IDCB, Faria Neto JR, Kato JT, Bertolami MC, Miname MH, Castelo MHCG, Lavrador MSF, Machado RM, Souza PGD, Alves RJ, Machado VA, Salgado Filho W. Update of the Brazilian Guideline for Familial Hypercholesterolemia - 2021. Arq Bras Cardiol 2021; 117:782-844. [PMID: 34709306 PMCID: PMC8528358 DOI: 10.36660/abc.20210788] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
| | - Viviane Zorzanelli Rocha Giraldez
- Instituto do Coração (InCor) da Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
- Grupo Fleury, São Paulo, SP - Brasil
| | | | | | - Ana Maria Lottenberg
- Hospital Israelita Albert Einstein (HIAE) - Faculdade Israelita de Ciências da Saúde Albert Einstein (FICSAE), São Paulo, SP - Brasil
- Faculdade de Medicina da Universidade de São Paulo, Laboratório de Lípides (LIM10), São Paulo, São Paulo, SP - Brasil
| | | | | | - Ana Paula M Chacra
- Instituto do Coração (InCor) da Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
| | | | | | | | | | - Andrei C Sposito
- Universidade Estadual de Campinas (UNICAMP), Campinas, SP - Brasil
| | | | - Cinthia Elim Jannes
- Instituto do Coração (InCor) da Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
| | | | | | | | | | - Fernando Cesena
- Hospital Israelita Albert Einstein (HIAE), São Paulo, SP - Brasil
| | | | | | | | | | | | | | - Marcio Hiroshi Miname
- Instituto do Coração (InCor) da Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
| | - Maria Helane Costa Gurgel Castelo
- Universidade Federal do Ceará (UFC), Fortaleza, CE - Brasil
- Hospital do Coração de Messejana, Fortaleza, CE - Brasil
- Professora da Faculdade Unichristus, Fortaleza, CE - Brasil
| | - Maria Sílvia Ferrari Lavrador
- Hospital Israelita Albert Einstein (HIAE) - Faculdade Israelita de Ciências da Saúde Albert Einstein (FICSAE), São Paulo, SP - Brasil
| | - Roberta Marcondes Machado
- Faculdade de Medicina da Universidade de São Paulo, Laboratório de Lípides (LIM10), São Paulo, São Paulo, SP - Brasil
| | - Patrícia Guedes de Souza
- Hospital Universitário Professor Edgard Santos da Universidade Federal da Bahia (UFBA), Salvador, BA - Brasil
| | | | | | - Wilson Salgado Filho
- Instituto do Coração (InCor) da Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
| |
Collapse
|
12
|
Abstract
Dyslipidemias are a group of diseases, which are characterized by abnormal blood concentrations of cholesterol, triglycerides and/or low-density lipoprotein-cholesterol (LDL-c). Dyslipidemia is a determinant condition for the progress of an atherosclerotic plaque formation. The resulting atherogenicity is due to at least two mechanisms: first, to the accumulation in the plasma of lipid particles that have the capacity to alter the function of the endothelium and deposit at the atheromatous plaque, and second, at an insufficient concentration of multifactorial type of high density lipoprotein-cholesterol (HDL-c), whose function is to protect against the development of atherosclerosis. Its highest prevalence is encountered among individuals with diabetes, hypertension or overweight. Hyperlipidemia is one of the main predisposing factors for the development of cardiovascular disease. Hyperlipidemia can be the result of a genetic condition, the secondary expression of a primary process or the consequence of exogenous factors (food, cultural, socio-economic, etc.), all of which lead to the elevation of plasma lipid levels. The objective of this study was to carry out an analysis of the genes involved in the development of dyslipidemias that lead to cardiovascular disease with special emphasis on the proprotein convertase subtilin/kexin type 9 (PCSK9) gene. The PCSK9 gene participates in the development of primary dyslipidemias, mainly familial hypercholesterolemia, currently the pharmacological treatment of choice to reduce LDL-c are statins, however, it has been observed that these have been insufficient to eliminate cardiovascular risk, especially in subjects with primary forms of hypercholesterolemia related to genetic mutations, or statin intolerance.
Collapse
|
13
|
PCSK9: A Multi-Faceted Protein That Is Involved in Cardiovascular Biology. Biomedicines 2021; 9:biomedicines9070793. [PMID: 34356856 PMCID: PMC8301306 DOI: 10.3390/biomedicines9070793] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 12/29/2022] Open
Abstract
Pro-protein convertase subtilisin/kexin type 9 (PCSK9) is secreted mostly by hepatocytes and to a lesser extent by the intestine, pancreas, kidney, adipose tissue, and vascular cells. PCSK9 has been known to interact with the low-density lipoprotein receptor (LDLR) and chaperones the receptor to its degradation. In this manner, targeting PCSK9 is a novel attractive approach to reduce hyperlipidaemia and the risk for cardiovascular diseases. Recently, it has been recognised that the effects of PCSK9 in relation to cardiovascular complications are not only LDLR related, but that various LDLR-independent pathways and processes are also influenced. In this review, the various LDLR dependent and especially independent effects of PCSK9 on the cardiovascular system are discussed, followed by an overview of related PCSK9-polymorphisms and currently available and future therapeutic approaches to manipulate PCSK9 expression.
Collapse
|
14
|
Alves AC, Azevedo S, Benito-Vicente A, Graça R, Galicia-Garcia U, Barros P, Jordan P, Martin C, Bourbon M. LDLR variants functional characterization: Contribution to variant classification. Atherosclerosis 2021; 329:14-21. [PMID: 34167030 DOI: 10.1016/j.atherosclerosis.2021.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/28/2021] [Accepted: 06/02/2021] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIMS Familial hypercholesterolaemia (FH) is an autosomal disorder of lipid metabolism presenting with increased cardiovascular risk. LDLR mutations are the cause of disease in 90% of the cases but functional studies have only been performed for about 15% of all LDLR variants. In the Portuguese Familial Hypercholesterolemia Study (PFHS), 142 unique LDLR alterations were identified and 44 (30%) lack functional characterization. The aim of the present work is to increase evidence for variant classification by performing functional characterization of 13 LDLR missense alterations found in Portugal and in 20 other countries. METHODS Different LDLR mutants were generated by site-directed mutagenesis and expressed in CHO-ldlA7 cells lacking endogenous expression of LDLR. To determine the effects of alterations on LDLR function, cell surface expression, binding and uptake of FITC-LDL were assessed by flow cytometry and Western blot. RESULTS Of the 13 variants studied 7 were shown to affect LDLR function - expression, binding or uptake, with rates lower than 60%: p.(Cys184Tyr), p.(Gly207_Ser213del); p.(His211Asp); p.(Asp221Tyr); p.(Glu288Lys); p.(Gly592Glu) and p.(Asp601Val)). The remaining 6 variants do not alter the LDLR function. CONCLUSIONS These studies contributed to an update of these variants classification: from the 9 variants classified as variants of unknown significance, 7 have reached now a final classification and 3 variants have improved classification from likely pathogenic to pathogenic. In Portugal, an additional 55 patients received an FH definite diagnosis thanks to these studies. Since only likely pathogenic and pathogenic variants are clinically actionable, this work shows the importance of functional studies for variant classification.
Collapse
Affiliation(s)
- Ana Catarina Alves
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Sílvia Azevedo
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal
| | - Asier Benito-Vicente
- Biofisika Institute (UPV/EHU, CSIC) and Departamento de Bioquímica y Biología Molecular, Universidad Del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Rafael Graça
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Unai Galicia-Garcia
- Biofisika Institute (UPV/EHU, CSIC) and Departamento de Bioquímica y Biología Molecular, Universidad Del País Vasco, Apdo. 644, 48080, Bilbao, Spain; Department of Molecular Biophysics, Fundación Biofísica Bizkaia, 48940, Leioa, Spain
| | - Patrícia Barros
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal; Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal
| | - Peter Jordan
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal; Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal
| | - Cesar Martin
- Biofisika Institute (UPV/EHU, CSIC) and Departamento de Bioquímica y Biología Molecular, Universidad Del País Vasco, Apdo. 644, 48080, Bilbao, Spain
| | - Mafalda Bourbon
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
| |
Collapse
|
15
|
Gazzotti M, Casula M, Olmastroni E, Averna M, Arca M, Catapano AL. How registers could enhance knowledge and characterization of genetic dyslipidaemias: The experience of the LIPIGEN in Italy and of other networks for familial hypercholesterolemia. ATHEROSCLEROSIS SUPP 2020; 42:e35-e40. [PMID: 33589222 DOI: 10.1016/j.atherosclerosissup.2021.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Familial hypercholesterolemia (FH) is a common genetic disorder of lipid metabolism, still underdiagnosed and undertreated in the general population. Pathology registers could play a crucial role in the creation of a comprehensive and integrated global approach to cover all aspects of this disease. Systematic data collection of patients affected by FH has increased dramatically worldwide in the past few years. Moreover, results from registers already established for the longest time showed their potentialities in the implementation of the knowledge of FH, comparing country-specific approaches and providing real-world data about identification, management and treatment of FH individuals in the clinical practice. The potential fields of research through registers are related to the deepening of the genetic basis of disease, the study of genotype-phenotype correlation, the local adaption and implementation of diagnostic algorithms, the comparison of pharmacological approaches and treatment gaps in real-life clinical practice, the evaluation of specific subpopulations, and the identification of factors modifying cardiovascular disease risk. Registers could become also a valid resource for other rare dyslipidaemias, contributing towards the evidence-based enhancement in the worldwide care of uncommon diseases.
Collapse
Affiliation(s)
- Marta Gazzotti
- Epidemiology and Preventive Pharmacology Service (SEFAP), Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy.
| | - Manuela Casula
- Epidemiology and Preventive Pharmacology Service (SEFAP), Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy; IRCCS MultiMedica, Sesto San Giovanni (MI), Italy
| | - Elena Olmastroni
- Epidemiology and Preventive Pharmacology Service (SEFAP), Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Maurizio Averna
- Department ProMISE (Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties), University of Palermo, Palermo, Italy
| | - Marcello Arca
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Alberico L Catapano
- Epidemiology and Preventive Pharmacology Service (SEFAP), Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy; IRCCS MultiMedica, Sesto San Giovanni (MI), Italy
| |
Collapse
|
16
|
de Paiva Silvino JP, Jannes CE, Tada MT, Lima IR, Silva IDFO, Pereira AC, Gomes KB. Cascade screening and genetic diagnosis of familial hypercholesterolemia in clusters of the Southeastern region from Brazil. Mol Biol Rep 2020; 47:9279-9288. [PMID: 33231818 DOI: 10.1007/s11033-020-06014-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/16/2020] [Indexed: 01/04/2023]
Abstract
Familial hypercholesterolemia (FH) is an autosomal dominant genetic disease characterized by high levels of low-density lipoprotein-cholesterol (LDLc), associated to premature cardiovascular disease. The detection of the variants related to FH is important to improve the early diagnosis in probands / index-cases (ICs) and their relatives. We included ICs with FH and their relatives, living in a small region of Minas Gerais state-Brazil, which were classified according to Dutch Lipid Clinic Network Criteria (DLCNC) and submitted to sequencing of genes related to FH (LDLR, APOB, PCSK9, LDLRAP1, LIPA, STAP1, APOE, ABCG5 e ABCG8). In a total of 143 subjects (32 ICs and 111 relatives), eight variants were identified in 91 individuals. From these variants, five were in LDLR [p.(Asp224Asn), p.(Ser854Gly), p.(Cys34Arg), p.(Asp601His), deletion of exon15 in LDLR)], one in APOB [p.(Met499Val)], one in PCSK9 [p.(Arg237Trp)] and one in APOE [p.(Pro28Leu)] genes. The variants were detected in 100% of those subjects classified as definitive, 87% as probable and 69% as possible FH cases based on DLCNC. The LDLc level was higher in individuals with corneal arch and xanthomas or xanthelasmas, as well as in pathogenic or probably pathogenic variants carriers. This study showed higher frequency of LDLR gene variants compared to other genes related to LDL metabolism in individuals with FH in Minas Gerais - Brazil and the presence of FH in relatives without previous diagnosis. Our data reinforce the importance of molecular and clinical evaluation of FH relatives in order to early diagnosis the FH, as well as cardiovascular diseases prevention.
Collapse
Affiliation(s)
| | - Cinthia Elim Jannes
- Laboratório de Genética e Cardiologia Molecular do Instituto do Coração de São Paulo (INCOR), Hospital das Clínicas da Universidade de São Paulo, São Paulo, Brazil
| | - Mauricio Teruo Tada
- Laboratório de Genética e Cardiologia Molecular do Instituto do Coração de São Paulo (INCOR), Hospital das Clínicas da Universidade de São Paulo, São Paulo, Brazil
| | - Isabella Ramos Lima
- Laboratório de Genética e Cardiologia Molecular do Instituto do Coração de São Paulo (INCOR), Hospital das Clínicas da Universidade de São Paulo, São Paulo, Brazil
| | - Iêda de Fátima Oliveira Silva
- Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, Brazil
| | - Alexandre Costa Pereira
- Laboratório de Genética e Cardiologia Molecular do Instituto do Coração de São Paulo (INCOR), Hospital das Clínicas da Universidade de São Paulo, São Paulo, Brazil
| | - Karina Braga Gomes
- Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerias, Brazil. .,Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
| |
Collapse
|
17
|
Guo Q, Feng X, Zhou Y. PCSK9 Variants in Familial Hypercholesterolemia: A Comprehensive Synopsis. Front Genet 2020; 11:1020. [PMID: 33173529 PMCID: PMC7538608 DOI: 10.3389/fgene.2020.01020] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 08/10/2020] [Indexed: 01/22/2023] Open
Abstract
Autosomal dominant familial hypercholesterolemia (FH) affects approximately 1/250, individuals and potentially leads to elevated blood cholesterol and a significantly increased risk of atherosclerosis. Along with improvements in detection and the increased early diagnosis and treatment, the serious burden of FH on families and society has become increasingly apparent. Since FH is strongly associated with proprotein convertase subtilisin/kexin type 9 (PCSK9), increasing numbers of studies have focused on finding effective diagnostic and therapeutic methods based on PCSK9. At present, as PCSK9 is one of the main pathogenic FH genes, its contribution to FH deserves more explorative research.
Collapse
Affiliation(s)
- Qianyun Guo
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
| | - Xunxun Feng
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
| | - Yujie Zhou
- Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Department of Cardiology, Beijing Anzhen Hospital, Clinical Center for Coronary Heart Disease, Beijing Institute of Heart Lung and Blood Vessel Disease, Capital Medical University, Beijing, China
| |
Collapse
|
18
|
Mutation type classification and pathogenicity assignment of sixteen missense variants located in the EGF-precursor homology domain of the LDLR. Sci Rep 2020; 10:1727. [PMID: 32015373 PMCID: PMC6997160 DOI: 10.1038/s41598-020-58734-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 01/21/2020] [Indexed: 12/21/2022] Open
Abstract
The primary genetic cause of familial hypercholesterolemia (FH) is related to mutations in the LDLR gene encoding the Low-density Lipoprotein Receptor. LDLR structure is organized in 5 different domains, including an EGF-precursor homology domain that plays a pivotal role in lipoprotein release and receptor recycling. Mutations in this domain constitute 51.7% of the total missense variants described in LDLR. The aim of the present work was to analyse how clinically significant variants in the EGF-precursor homology domain impact LDLR. The activity of sixteen LDLR variants was functionally characterized by determining LDLR expression by Western blot and LDLR expression, LDL binding capacity and uptake, and LDLR recycling activity by flow cytometry in transfected CHO-ldlA7 cells. Of the analysed variants, we found six non-pathogenic LDLR variants and ten pathogenic variants distributed as follow: three class 3 variants; four class 2 variants; and three class 5 variants. These results can be incorporated into clinical management of patients by helping guide the appropriate level of treatment intensity depending on the extent of loss of LDLR activity. This data can also contribute to cascade-screening for pathogenic FH variants.
Collapse
|
19
|
Khoury E, Brisson D, Gaudet D. Preclinical discovery and development of evolocumab for the treatment of hypercholesterolemia. Expert Opin Drug Discov 2020; 15:403-414. [DOI: 10.1080/17460441.2020.1704728] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Etienne Khoury
- Clinical Lipidology and Rare Lipid Disorders Unit, Community Genomic Medicine Center, Department of Medicine, Université de Montréal and ECOGENE-21 Clinical and Translational Research Center, Chicoutimi, Québec, Canada
| | - Diane Brisson
- Clinical Lipidology and Rare Lipid Disorders Unit, Community Genomic Medicine Center, Department of Medicine, Université de Montréal and ECOGENE-21 Clinical and Translational Research Center, Chicoutimi, Québec, Canada
| | - Daniel Gaudet
- Clinical Lipidology and Rare Lipid Disorders Unit, Community Genomic Medicine Center, Department of Medicine, Université de Montréal and ECOGENE-21 Clinical and Translational Research Center, Chicoutimi, Québec, Canada
- Lipid Clinic, Chicoutimi Hospital, Chicoutimi, Québec, Canada
| |
Collapse
|
20
|
Ginsburg GS, Wu RR, Orlando LA. Family health history: underused for actionable risk assessment. Lancet 2019; 394:596-603. [PMID: 31395442 PMCID: PMC6822265 DOI: 10.1016/s0140-6736(19)31275-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 04/04/2019] [Accepted: 05/16/2019] [Indexed: 01/04/2023]
Abstract
Family health history (FHH) is the most useful means of assessing risk for common chronic diseases. The odds ratio for risk of developing disease with a positive FHH is frequently greater than 2, and actions can be taken to mitigate risk by adhering to screening guidelines, genetic counselling, genetic risk testing, and other screening methods. Challenges to the routine acquisition of FHH include constraints on provider time to collect data and the difficulty in accessing risk calculators. Disease-specific and broader risk assessment software platforms have been developed, many with clinical decision support and informatics interoperability, but few access patient information directly. Software that allows integration of FHH with the electronic medical record and clinical decision support capabilities has provided solutions to many of these challenges. Patient facing, electronic medical record, and web-enabled FHH platforms have been developed, and can provide greater identification of risk compared with conventional FHH ascertainment in primary care. FHH, along with cascade screening, can be an important component of population health management approaches to overall reduction of risk.
Collapse
Affiliation(s)
- Geoffrey S Ginsburg
- Duke Center for Applied Genomics & Precision Medicine, Department of Medicine, Duke University School of Medicine, Durham, NC, USA.
| | - R Ryanne Wu
- Duke Center for Applied Genomics & Precision Medicine, Department of Medicine, Duke University School of Medicine, Durham, NC, USA; Durham Veteran Affairs Cooperative Studies Program Epidemiology Center, Durham, NC, USA
| | - Lori A Orlando
- Duke Center for Applied Genomics & Precision Medicine, Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
21
|
Lu X. Structure and Function of Proprotein Convertase Subtilisin/kexin Type 9 (PCSK9) in Hyperlipidemia and Atherosclerosis. Curr Drug Targets 2019; 20:1029-1040. [DOI: 10.2174/1389450120666190214141626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 02/01/2023]
Abstract
Background:One of the important factors in Low-Density Lipoprotein (LDL) metabolism is the LDL receptor (LDLR) by its capacity to bind and subsequently clear cholesterol derived from LDL (LDL-C) in the circulation. Proprotein Convertase Subtilisin-like Kexin type 9 (PCSK9) is a newly discovered serine protease that destroys LDLR in the liver and thereby controls the levels of LDL in plasma. Inhibition of PCSK9-mediated degradation of LDLR has, therefore, become a novel target for lipid-lowering therapy.Methods:We review the current understanding of the structure and function of PCSK9 as well as its implications for the treatment of hyperlipidemia and atherosclerosis.Results:New treatments such as monoclonal antibodies against PCSK9 may be useful agents to lower plasma levels of LDL and hence prevent atherosclerosis.Conclusion:PCSK9's mechanism of action is not yet fully clarified. However, treatments that target PCSK9 have shown striking early efficacy and promise to improve the lives of countless patients with hyperlipidemia and atherosclerosis.
Collapse
Affiliation(s)
- Xinjie Lu
- The Mary and Garry Weston Molecular Immunology Laboratory, Thrombosis Research Institute, London, SW3 6LR, United Kingdom
| |
Collapse
|
22
|
Mohd Nor NS, Al-Khateeb AM, Chua YA, Mohd Kasim NA, Mohd Nawawi H. Heterozygous familial hypercholesterolaemia in a pair of identical twins: a case report and updated review. BMC Pediatr 2019; 19:106. [PMID: 30975109 PMCID: PMC6458607 DOI: 10.1186/s12887-019-1474-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 03/28/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Familial hypercholesterolaemia (FH) is the most common inherited metabolic disease with an autosomal dominant mode of inheritance. It is characterised by raised serum levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-c), leading to premature coronary artery disease. Children with FH are subjected to early and enhanced atherosclerosis, leading to greater risk of coronary events, including premature coronary artery disease. To the best of our knowledge, this is the first report of a pair of monochorionic diamniotic identical twins with a diagnosis of heterozygous FH, resulting from mutations in both LDLR and ABCG8 genes. CASE PRESENTATION This is a rare case of a pair of 8-year-old monochorionic diamniotic identical twin, who on family cascade screening were diagnosed as definite FH, according to the Dutch Lipid Clinic Criteria (DLCC) with a score of 10. There were no lipid stigmata noted. Baseline lipid profiles revealed severe hypercholesterolaemia, (TC = 10.5 mmol/L, 10.6 mmol/L; LDL-c = 8.8 mmol/L, 8.6 mmol/L respectively). Their father is the index case who initially presented with premature CAD, and subsequently diagnosed as FH. Family cascade screening identified clinical FH in other family members including their paternal grandfather who also had premature CAD, and another elder brother, aged 10 years. Genetic analysis by targeted next-generation sequencing using MiSeq platform (Illumina) was performed to detect mutations in LDLR, APOB100, PCSK9, ABCG5, ABCG8, APOE and LDLRAP1 genes. Results revealed that the twin, their elder brother, father and grandfather are heterozygous for a missense mutation (c.530C > T) in LDLR that was previously reported as a pathogenic mutation. In addition, the twin has heterozygous ABCG8 gene mutation (c.55G > C). Their eldest brother aged 12 years and their mother both had normal lipid profiles with absence of LDLR gene mutation. CONCLUSION A rare case of Asian monochorionic diamniotic identical twin, with clinically diagnosed and molecularly confirmed heterozygous FH, due to LDLR and ABCG8 gene mutations have been reported. Childhood FH may not present with the classical physical manifestations including the pathognomonic lipid stigmata as in adults. Therefore, childhood FH can be diagnosed early using a combination of clinical criteria and molecular analyses.
Collapse
Affiliation(s)
- Noor Shafina Mohd Nor
- Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia.,Departments of Paediatric, Biochemistry and Chemical Pathology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000, Sungai Buloh, Selangor, Malaysia
| | - Alyaa Mahmood Al-Khateeb
- Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia.,Departments of Paediatric, Biochemistry and Chemical Pathology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000, Sungai Buloh, Selangor, Malaysia
| | - Yung-An Chua
- Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia
| | - Noor Alicezah Mohd Kasim
- Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia.,Departments of Paediatric, Biochemistry and Chemical Pathology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000, Sungai Buloh, Selangor, Malaysia
| | - Hapizah Mohd Nawawi
- Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia. .,Departments of Paediatric, Biochemistry and Chemical Pathology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000, Sungai Buloh, Selangor, Malaysia.
| |
Collapse
|
23
|
Alhababi D, Zayed H. Spectrum of mutations of familial hypercholesterolemia in the 22 Arab countries. Atherosclerosis 2018; 279:62-72. [PMID: 30415195 DOI: 10.1016/j.atherosclerosis.2018.10.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 10/15/2018] [Accepted: 10/18/2018] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND AIMS Familial hypercholesterolemia (FH) is an inherited genetic disorder of lipid metabolism characterized by a high serum LDL-cholesterol profile and xanthoma formation, and FH increases the risk of premature atherosclerosis and cardiovascular disease (CVD). Mutations in the low-density lipoprotein (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin 9 (PCSK9), and LDLRAP1 genes have been associated with FH. Although FH is a major risk for CVD, the disease prevalence and its underlying molecular basis in the 22 Arab countries are still understudied. This study aimed to analyze all peer-reviewed studies related to the prevalence of FH and its causative mutations in the 22 Arab countries. METHODS We searched five literature databases (Scopus, Science Direct, Web of Science, PubMed, and Google Scholar) from inception until June 2018, using all possible search terms to capture all of the genetic and prevalence data related to Arab patients with FH. RESULTS A total of 5,484 titles and abstracts were identified; 51 studies met our inclusion criteria for the final systematic review. Fifty-one mutations in Arab patients with FH were identified in only eight Arab countries; 47 were identified in the LDLR gene, two in the PCSK9 gene, and two in LDLRAP1 gene. Twenty mutations in the LDLR gene were distinctive to Arab patients. A few studies reported prevalence estimates, ranging from 0.4% to 6.8%. CONCLUSIONS This is the first systematic review to dissect the up-to-date status of the genetic epidemiology of Arab patients with FH. It seems that FH is underdiagnosed and that its prevalence is understudied due to the dearth of published information about Arab patients with FH. Therefore, there is a need for well-controlled genetic epidemiological studies on Arab patients with FH.
Collapse
Affiliation(s)
- Dalal Alhababi
- College of Health Sciences, Biomedical Program, Qatar University, Doha, Qatar
| | - Hatem Zayed
- College of Health Sciences, Biomedical Program, Qatar University, Doha, Qatar.
| |
Collapse
|
24
|
Further evidence of novel APOB mutations as a cause of familial hypercholesterolaemia. Atherosclerosis 2018; 277:448-456. [DOI: 10.1016/j.atherosclerosis.2018.06.819] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/06/2018] [Accepted: 06/14/2018] [Indexed: 01/02/2023]
|
25
|
Martín-Campos JM, Plana N, Figueras R, Ibarretxe D, Caixàs A, Esteve E, Pérez A, Bueno M, Mauri M, Roig R, Martínez S, Pintó X, Masana L, Julve J, Blanco-Vaca F. Autosomal dominant hypercholesterolemia in Catalonia: Correspondence between clinical-biochemical and genetic diagnostics in 967 patients studied in a multicenter clinical setting. J Clin Lipidol 2018; 12:1452-1462. [PMID: 30293936 DOI: 10.1016/j.jacl.2018.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 08/30/2018] [Accepted: 09/04/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Autosomal dominant hypercholesterolemia (ADH) is associated with mutations in the low-density lipoprotein (LDL) receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) genes, and it is estimated to be greatly underdiagnosed. The most cost-effective strategy for increasing ADH diagnosis is a cascade screening from mutation-positive probands. OBJECTIVE The objective of this study was to evaluate the results from 2008 to 2016 of ADH genetic analysis performed in our clinical laboratory, serving most lipid units of Catalonia, a Spanish region with approximately 7.5 million inhabitants. METHODS After the application of the Dutch Lipid Clinic Network (DLCN) clinical diagnostic score for ADH, this information and blood or saliva from 23 different lipid clinic units were investigated in our laboratory. DNA was screened for mutations in LDLR, APOB, and PCSK9, using the DNA-array LIPOchip, the next-generation sequencing SEQPRO LIPO RS platform, and multiplex ligation-dependent probe amplification (MLPA). The Simon Broome Register Group (SBRG) criteria was calculated and analyzed for comparative purposes. RESULTS A total of 967 unrelated samples were analyzed. From this, 158 pathogenic variants were detected in 356 patients. The main components of the DLCN criteria associated with the presence of mutation were plasma LDL cholesterol (LDLc), age, and the presence of tendinous xanthomata. The contribution of family history to the diagnosis was lower than in other studies. DLCN and SBRG were similarly useful for predicting the presence of mutation. CONCLUSION In a real clinical practice, multicenter setting in Catalonia, the percentage of positive genetic diagnosis in patients potentially affected by ADH was 38.6%. The DLCN showed a relatively low capacity to predict mutation detection but a higher one for ruling out mutation.
Collapse
Affiliation(s)
- Jesús M Martín-Campos
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain.
| | - Núria Plana
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Rosaura Figueras
- Hospital Universitari de Bellvitge, Servei de Medicina Interna, Unitat de Lípids i Risc Vascular, Universitat de Barcelona, IDIBELL, CIBEROBN, FIPEC, ABS 17 de Setembre, L'Hospitalet/El Prat de Llobregat, Spain
| | - Daiana Ibarretxe
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Assumpta Caixàs
- Hospital Universitari Parc Taulí, Servei d'Endocrinologia i Nutrició, Institut Investigació i Innovació Parc Taulí I3PT-Universitat Autònoma de Barcelona, Sabadell, Spain
| | - Eduardo Esteve
- Hospital Universitari de Girona Dr Josep Trueta, Servei d'Endocrinologia i Nutrició, CIBEROBN, Girona, Spain
| | - Antonio Pérez
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Marta Bueno
- Hospital Universitari Arnau de Vilanova, Servei d'Endocrinologia i Nutrició, Lleida, Spain
| | - Marta Mauri
- Hospital de Terrassa, Servei de Medicina Interna, Terrassa, Spain
| | - Rosa Roig
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Susana Martínez
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Xavier Pintó
- Hospital Universitari de Bellvitge, Servei de Medicina Interna, Unitat de Lípids i Risc Vascular, Universitat de Barcelona, IDIBELL, CIBEROBN, FIPEC, ABS 17 de Setembre, L'Hospitalet/El Prat de Llobregat, Spain
| | - Luís Masana
- Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Unitat de Medicina Vascular i Metabolisme, Unitat de Recerca en Lípids i Arteriosclerosi, IISPV, CIBERDEM, Reus, Spain
| | - Josep Julve
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain
| | - Francisco Blanco-Vaca
- Institut de Recerca - Hospital de la Santa Creu i Sant Pau, Serveis de Bioquímica, i d'Endocrinologia i Nutrició, IIB Sant Pau, CIBERDEM, Universitat Autònoma de Barcelona, Departaments de Bioquímica i Biologia Molecular, i Medicina, Barcelona, Spain.
| | | |
Collapse
|
26
|
|
27
|
Wu X, Pang J, Wang X, Peng J, Chen Y, Wang S, Watts GF, Lin J. Reverse cascade screening for familial hypercholesterolemia in high-risk Chinese families. Clin Cardiol 2017; 40:1169-1173. [PMID: 29168983 PMCID: PMC6490610 DOI: 10.1002/clc.22809] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 08/29/2017] [Accepted: 09/04/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Reverse cascade screening is not commonly employed to detect new cases of familial hypercholesterolemia (FH). We aimed to assess the outcome of this screening strategy in families in which the probands were children with severe FH. HYPOTHESIS Reverse cascade screening is an effective method to detect new patients with FH. METHODS Reverse cascade screening was undertaken starting from 47 index children with severe hypercholesterolemia; 39 were homozygous/compound heterozygous FH and 8 were heterozygous FH. Available parents, siblings, and second-degree relatives were contacted and screened. RESULTS From the 39 cases of homozygous/compound heterozygous FH, 80 first-degree family members were available for screening; 70 were parents and 10 were siblings. All first-degree relatives screened were genetically diagnosed with FH. None of the parents had been treated with statins at the time of diagnosis, and 10 (12.7%) had premature coronary artery disease. Additionally, 46 second-degree relatives were screened, of which 41 (89%) were diagnosed with FH. From the 8 heterozygous FH children, 17 first- and second-degree relatives were screened and 12 new cases of FH were also diagnosed. Hence, the overall diagnostic yield of screening was 2.8 new cases of FH per index case. CONCLUSIONS Reverse cascade screening is a highly effective method for diagnosing new cases of FH in parents, siblings, and second-degree relatives of index children with severe FH.
Collapse
Affiliation(s)
- Xue Wu
- Beijing Anzhen Hospital, Capital Medical University–Beijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina
| | - Jing Pang
- School of Medicine, Faculty of Health and Medical ScienceUniversity of Western AustraliaPerthAustralia
| | - Xumin Wang
- Beijing Institute of GenomicsChinese Academy of SciencesBeijingChina
| | - Jie Peng
- Beijing Anzhen Hospital, Capital Medical University–Beijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina
| | - Yan Chen
- Department of CardiologyTianjin Chest HospitalTianjinChina
| | - Shilong Wang
- Beijing Anzhen Hospital, Capital Medical University–Beijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina
| | - Gerald F. Watts
- School of Medicine, Faculty of Health and Medical ScienceUniversity of Western AustraliaPerthAustralia
- Lipid Disorders Clinic, Cardiometabolic Service, Department of CardiologyRoyal Perth HospitalPerthAustralia
| | - Jie Lin
- Beijing Anzhen Hospital, Capital Medical University–Beijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina
- Department of Atherosclerosis, Beijing Anzhen HospitalCapital Medical UniversityBeijingChina
| |
Collapse
|
28
|
Chora JR, Medeiros AM, Alves AC, Bourbon M. Analysis of publicly available LDLR, APOB, and PCSK9 variants associated with familial hypercholesterolemia: application of ACMG guidelines and implications for familial hypercholesterolemia diagnosis. Genet Med 2017; 20:591-598. [PMID: 29261184 DOI: 10.1038/gim.2017.151] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 07/26/2017] [Indexed: 01/15/2023] Open
Abstract
PurposeFamilial hypercholesterolemia (FH) is an autosomal disorder of lipid metabolism presenting with increased cardiovascular risk. Although more than 1,700 variants have been associated with FH, the great majority have not been functionally proved to affect the low-density lipoprotein receptor cycle. We aimed to classify all described variants associated with FH and to establish the proportion of variants that lack evidence to support their pathogenicity.MethodsWe followed American College of Medical Genetics and Genomics (ACMG) guidelines for the classification, and collected information from a variety of databases and individual reports. A worldwide overview of publicly available FH variants was also performed.ResultsA total of 2,104 unique variants were identified as being associated with FH, but only 166 variants have been proven by complete in vitro functional studies to be causative of disease. Additionally, applying the ACMG guidelines, 1,097 variants were considered pathogenic or likely pathogenic. Only seven variants were found in all five continents.ConclusionThe lack of functional evidence for about 85% of all variants found in FH patients can compromise FH diagnosis and patient prognosis. ACMG classification improves variant interpretation, but functional studies are necessary to understand the effect of about 40% of all variants reported. Nevertheless, ACMG guidelines need to be adapted to FH for a better diagnosis.
Collapse
Affiliation(s)
- Joana Rita Chora
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisbon, Portugal.,University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisbon, Portugal
| | - Ana Margarida Medeiros
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisbon, Portugal.,University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisbon, Portugal
| | - Ana Catarina Alves
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisbon, Portugal.,University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisbon, Portugal
| | - Mafalda Bourbon
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisbon, Portugal.,University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisbon, Portugal
| |
Collapse
|
29
|
Bourbon M, Alves AC, Alonso R, Mata N, Aguiar P, Padró T, Mata P. Mutational analysis and genotype-phenotype relation in familial hypercholesterolemia: The SAFEHEART registry. Atherosclerosis 2017; 262:8-13. [DOI: 10.1016/j.atherosclerosis.2017.04.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 03/29/2017] [Accepted: 04/05/2017] [Indexed: 12/26/2022]
|
30
|
Calandra S, Tarugi P, Bertolini S. Impact of rare variants in autosomal dominant hypercholesterolemia causing genes. Curr Opin Lipidol 2017; 28:267-272. [PMID: 28323660 DOI: 10.1097/mol.0000000000000414] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW The systematic analysis of the major candidate genes in autosomal dominant hypercholesterolemia (ADH) and the use of next-generation sequencing (NGS) technology have made possible the discovery of several rare gene variants whose pathogenic effect in most cases remains poorly defined. RECENT FINDINGS One major advance in the field has been the adoption of a set of international guidelines for the assignment of pathogenicity to low-density lipoprotein receptor (LDLR) gene variants based on the use of softwares, complemented with data available from literature and public databases. The clinical impact of several novel rare variants in LDLR, APOB, PCSK9, APOE genes have been reported in large studies describing patients with ADH found to be homozygotes/compound heterozygotes, double heterozygotes, or simple heterozygotes. In-vitro functional studies have been conducted to clarify the effect of some rare ApoB variants on LDL binding to LDLR and the impact of a rare ApoE variant on the uptake of VLDL and LDL by hepatocytes. SUMMARY The update of the ADH gene variants database and the classification of variants in categories of pathogenicity is a major advance in the understanding the pathophysiology of ADH and in the management of this disorder. The studies of molecularly characterized patients with ADH have emphasized the impact of a specific variant and the variable clinical expression of different genotypes. The functional studies of some variants have increased our understanding of the molecular bases of some forms of ADH.
Collapse
Affiliation(s)
- Sebastiano Calandra
- aDepartment of Biomedical, Metabolic and Neural Sciences bDepartment of Life Sciences, University of Modena and Reggio Emilia, Modena cDepartment of Internal Medicine, University of Genova, Genova, Italy
| | | | | |
Collapse
|
31
|
Bourbon M, Alves AC, Sijbrands EJ. Low-density lipoprotein receptor mutational analysis in diagnosis of familial hypercholesterolemia. Curr Opin Lipidol 2017; 28:120-129. [PMID: 28169869 DOI: 10.1097/mol.0000000000000404] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
PURPOSE OF REVIEW To present up to date evidence on the pathogenicity of low-density lipoprotein receptor (LDLR) variants and to propose a strategy that is suitable for implementation in the clinical work-up of familial hypercholesterolaemia. RECENT FINDINGS More than 1800 variants have been described in the LDLR gene of patients with a clinical diagnosis of familial hypercholesterolaemia; however, less than 15% have functional evidence of pathogenicity. SUMMARY The spectrum of variants in the LDLR identified in patients with clinical familial hypercholesterolaemia is increasing as novel variants are still being reported. However, over 50% of all LDLR variants need further evidence before they can be confirmed as mutations causing disease. Even with applying the recent American College of Medical Genetics variant classification, a large number of variants are still considered variants of unknown significance. Before obtaining an undisputable confirmation of the effect on the expression and activity of the LDLR, reporting these variants as part of a clinical diagnosis to the patient holds the risk that it might need to be withdrawn in a later stage. An investment should be made to develop functional assays to characterize LDLR variants of unknown significance for a better patient diagnosis and to prevent confusion in the physician's office.
Collapse
Affiliation(s)
- Mafalda Bourbon
- aUnidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge bBioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal cDepartment of internal Medicine, Erasmus University Rotterdam, Rotterdam, the Netherlands
| | | | | |
Collapse
|
32
|
Seidah NG, Abifadel M, Prost S, Boileau C, Prat A. The Proprotein Convertases in Hypercholesterolemia and Cardiovascular Diseases: Emphasis on Proprotein Convertase Subtilisin/Kexin 9. Pharmacol Rev 2016; 69:33-52. [DOI: 10.1124/pr.116.012989] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
|
33
|
Leigh S, Futema M, Whittall R, Taylor-Beadling A, Williams M, den Dunnen JT, Humphries SE. The UCL low-density lipoprotein receptor gene variant database: pathogenicity update. J Med Genet 2016; 54:217-223. [PMID: 27821657 PMCID: PMC5502305 DOI: 10.1136/jmedgenet-2016-104054] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 10/06/2016] [Indexed: 12/04/2022]
Abstract
Background Familial hypercholesterolaemia (OMIM 143890) is most frequently caused by variations in the low-density lipoprotein receptor (LDLR) gene. Predicting whether novel variants are pathogenic may not be straightforward, especially for missense and synonymous variants. In 2013, the Association of Clinical Genetic Scientists published guidelines for the classification of variants, with categories 1 and 2 representing clearly not or unlikely pathogenic, respectively, 3 representing variants of unknown significance (VUS), and 4 and 5 representing likely to be or clearly pathogenic, respectively. Here, we update the University College London (UCL) LDLR variant database according to these guidelines. Methods PubMed searches and alerts were used to identify novel LDLR variants for inclusion in the database. Standard in silico tools were used to predict potential pathogenicity. Variants were designated as class 4/5 only when the predictions from the different programs were concordant and as class 3 when predictions were discordant. Results The updated database (http://www.lovd.nl/LDLR) now includes 2925 curated variants, representing 1707 independent events. All 129 nonsense variants, 337 small frame-shifting and 117/118 large rearrangements were classified as 4 or 5. Of the 795 missense variants, 115 were in classes 1 and 2, 605 in class 4 and 75 in class 3. 111/181 intronic variants, 4/34 synonymous variants and 14/37 promoter variants were assigned to classes 4 or 5. Overall, 112 (7%) of reported variants were class 3. Conclusions This study updates the LDLR variant database and identifies a number of reported VUS where additional family and in vitro studies will be required to confirm or refute their pathogenicity.
Collapse
Affiliation(s)
- Sarah Leigh
- Centre for Cardiovascular Genetics, Institute of Cardiovascular Sciences, University College London, London, UK
| | - Marta Futema
- Centre for Cardiovascular Genetics, Institute of Cardiovascular Sciences, University College London, London, UK
| | - Ros Whittall
- Centre for Cardiovascular Genetics, Institute of Cardiovascular Sciences, University College London, London, UK
| | | | - Maggie Williams
- Bristol Genetics Laboratory, Pathology Sciences, Blood Sciences and Bristol Genetics, Southmead Hospital, Bristol, UK
| | - Johan T den Dunnen
- Clinical Genetics and Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Steve E Humphries
- Centre for Cardiovascular Genetics, Institute of Cardiovascular Sciences, University College London, London, UK
| |
Collapse
|
34
|
Setia N, Saxena R, Arora A, Verma IC. Spectrum of mutations in homozygous familial hypercholesterolemia in India, with four novel mutations. Atherosclerosis 2016; 255:31-36. [PMID: 27816806 DOI: 10.1016/j.atherosclerosis.2016.10.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND AIMS Homozygous familial hypercholesterolemia (FH) is a rare but serious, inherited disorder of lipid metabolism characterized by very high total and LDL cholesterol levels from birth. It presents as cutaneous and tendon xanthomas since childhood, with or without cardiac involvement. FH is commonly caused by mutations in three genes, i.e. LDL receptor (LDLR), apolipoprotein B (ApoB) and PCSK9. We aimed to determine the spectrum of mutations in cases of homozygous FH in Asian Indians and evaluate if there was any similarity to the mutations observed in Caucasians. METHODS Sixteen homozygous FH subjects from eleven families were analyzed for mutations by Sanger sequencing. Large rearrangements in LDLR gene were evaluated by multiplex ligation probe dependent amplification (MLPA) technique. RESULTS Ten mutations were observed in LDLR gene, of which four mutations were novel. No mutation was detected in ApoB gene and common PCSK9 mutation (p.D374Y). Fourteen cases had homozygous mutations; one had compound heterozygous mutation, while no mutation was detected in one clinically homozygous case. We report an interesting "Triple hit" case with features of homozygous FH. CONCLUSIONS The spectrum of mutations in the Asian Indian population is quite heterogeneous. Of the mutations identified, 40% were novel. No mutation was observed in exons 3, 9 and 14 of LDLR gene, which are considered to be hot spots in studies done on Asian Indians in South Africa. Early detection followed by aggressive therapy, and cascade screening of extended families has been initiated to reduce the morbidity and mortality in these patients.
Collapse
Affiliation(s)
- Nitika Setia
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, 110060, India.
| | - Renu Saxena
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, 110060, India
| | - Anjali Arora
- Hyperlipidemia Prevention Clinic, Department of Cardiology, Sir Ganga Ram Hospital, New Delhi, 110060, India
| | - Ishwar C Verma
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, 110060, India
| |
Collapse
|
35
|
Elbitar S, Khoury PE, Ghaleb Y, Rabès JP, Varret M, Seidah NG, Boileau C, Abifadel M. Proprotein convertase subtilisin / kexin 9 (PCSK9) inhibitors and the future of dyslipidemia therapy: an updated patent review (2011-2015). Expert Opin Ther Pat 2016; 26:1377-1392. [DOI: 10.1080/13543776.2016.1206080] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Sandy Elbitar
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Laboratory of Biochemistry and Molecular Therapeutics, Faculty of Pharmacy, Pôle Technologie- Santé, Saint-Joseph University, Beirut, Lebanon
| | - Petra El Khoury
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Laboratory of Biochemistry and Molecular Therapeutics, Faculty of Pharmacy, Pôle Technologie- Santé, Saint-Joseph University, Beirut, Lebanon
| | - Youmna Ghaleb
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Laboratory of Biochemistry and Molecular Therapeutics, Faculty of Pharmacy, Pôle Technologie- Santé, Saint-Joseph University, Beirut, Lebanon
| | - Jean-Pierre Rabès
- Service de Biochimie et Génétique Moléculaire, AP-HP, Hôpitaux Universitaires Paris Ile-de-France Ouest, Site Ambroise Paré, Boulogne-Billancourt, France
- UFR des Sciences de la Santé Simone Veil, Université Versailles Saint-Quentin-en-Yvelines, Montigny-Le-Bretonneux, France
| | - Mathilde Varret
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Faculté de Médecine Paris 7, Université Denis Diderot, Paris, France
| | - Nabil G. Seidah
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, Montréal, Québec, Canada
| | - Catherine Boileau
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Faculté de Médecine Paris 7, Université Denis Diderot, Paris, France
- Département de Génétique, AP-HP, CHU Xavier Bichat, Paris, France
| | - Marianne Abifadel
- LVTS, INSERM U1148, Hôpital Xavier-Bichat, Paris, France
- Laboratory of Biochemistry and Molecular Therapeutics, Faculty of Pharmacy, Pôle Technologie- Santé, Saint-Joseph University, Beirut, Lebanon
| |
Collapse
|
36
|
Mollaki V, Drogari E. Genetic causes of monogenic familial hypercholesterolemia in the Greek population: Lessons, mistakes, and the way forward. J Clin Lipidol 2016; 10:748-756. [DOI: 10.1016/j.jacl.2016.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/19/2016] [Accepted: 02/20/2016] [Indexed: 10/22/2022]
|
37
|
Santos RD, Frauches TS, Chacra APM. Cascade Screening in Familial Hypercholesterolemia: Advancing Forward. J Atheroscler Thromb 2015. [PMID: 26194978 DOI: 10.5551/jat.31237] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Familial hypercholesterolemia is a genetic disorder associated with elevated LDL-cholesterol and high lifetime cardiovascular risk. Both clinical and molecular cascade screening programs have been implemented to increase early definition and treatment. In this systematic review, we discuss the main issues found in 65 different articles related to cascade screening and familial hypercholesterolemia, covering a range of topics including different types/strategies, considerations both positive and negative regarding cascade screening in general and associated with the different strategies, cost and coverage consideration, direct and indirect contact with patients, public policy around life insurance and doctor-patient confidentiality, the "right to know," and public health concerns regarding familial hypercholesterolemia.
Collapse
Affiliation(s)
- Raul D Santos
- Lipid Clinic, Heart Institute (InCor), University of São Paulo Medical School Hospital
| | | | | |
Collapse
|
38
|
Le QT, Blanchet M, Seidah NG, Labonté P. Plasma Membrane Tetraspanin CD81 Complexes with Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) and Low Density Lipoprotein Receptor (LDLR), and Its Levels Are Reduced by PCSK9. J Biol Chem 2015. [PMID: 26195630 DOI: 10.1074/jbc.m115.642991] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an important factor in plasma cholesterol regulation through modulation of low density lipoprotein receptor (LDLR) levels. Naturally occurring mutations can lead to hyper- or hypocholesterolemia in human. Recently, we reported that PCSK9 was also able to modulate CD81 in Huh7 cells. In the present study, several gain-of-function and loss-of-function mutants as well as engineered mutants of PCSK9 were compared for their ability to modulate the cell surface expression of LDLR and CD81. Although PCSK9 gain-of-function D374Y enhanced the degradation both receptors, D374H and D129N seemed to only reduce LDLR levels. In contrast, mutations in the C-terminal hinge-cysteine-histidine-rich domain segment primarily affected the PCSK9-induced CD81 degradation. Furthermore, when C-terminally fused to an ACE2 transmembrane anchor, the secretory N-terminal catalytic or hinge-cysteine-histidine-rich domain domains of PCSK9 were able to reduce CD81 and LDLR levels. These data confirm that PCSK9 reduces CD81 levels via an intracellular pathway as reported for LDLR. Using immunocytochemistry, a proximity ligation assay, and co-immunoprecipitation, we found that the cell surface level of PCSK9 was enhanced upon overexpression of CD81 and that both PCSK9 and LDLR interact with this tetraspanin protein. Interestingly, using CHO-A7 cells lacking LDLR expression, we revealed that LDLR was not required for the degradation of CD81 by PCSK9, but its presence strengthened the PCSK9 effect.
Collapse
Affiliation(s)
- Quoc-Tuan Le
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada, Department of Malaria, Parasitology and Entomology, Vietnam Military Medical University, 104 Phung Hung Street, Ha Dong District, Hanoi 151000, Vietnam, and
| | - Matthieu Blanchet
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada
| | - Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada
| | - Patrick Labonté
- From the Institut National de la Recherche Scientifique-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec H7V 1B7, Canada,
| |
Collapse
|
39
|
Living the PCSK9 adventure: from the identification of a new gene in familial hypercholesterolemia towards a potential new class of anticholesterol drugs. Curr Atheroscler Rep 2015; 16:439. [PMID: 25052769 DOI: 10.1007/s11883-014-0439-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A decade after our discovery of the involvement of proprotein convertase subtilisin/kexin type 9 (PCSK9) in cholesterol metabolism through the identification of the first mutations leading to hypercholesterolemia, PCSK9 has become one of the most promising targets in cholesterol and cardiovascular diseases. This challenging work in the genetics of hypercholesterolemia paved the way for a plethora of studies around the world allowing the characterization of PCSK9, its expression, its impact on reducing the abundance of LDL receptor, and the identification of loss-of-function mutations in hypocholesterolemia. We highlight the different steps of this adventure and review the published clinical trials especially those with the anti-PCSK9 antibodies evolocumab (AMG 145) and alirocumab (SAR236553/REGN727), which are in phase III trials. The promising results in lowering LDL cholesterol levels raise hope that the PCSK9 adventure will lead, after the large and long-term ongoing phase III studies evaluating efficacy and safety, to a new anticholesterol pharmacological class.
Collapse
|
40
|
The importance of an integrated analysis of clinical, molecular, and functional data for the genetic diagnosis of familial hypercholesterolemia. Genet Med 2015; 17:980-8. [PMID: 25741862 DOI: 10.1038/gim.2015.14] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 01/16/2015] [Indexed: 01/20/2023] Open
Abstract
PURPOSE Familial hypercholesterolemia (FH) is one of the most common monogenic disorders, and the high concentrations of low-density lipoprotein (LDL) cholesterol presented since birth confers on these patients an increased cardiovascular risk. More than 1,600 alterations have been described in the LDL receptor gene (LDLR), but a large number need to be validated as mutations causing disease to establish a diagnosis of FH. This study aims to characterize, both at the phenotypic and genotypic levels, families with a clinical diagnosis of FH and present evidence for the importance of the integration of clinical, molecular, and functional data for the correct diagnosis of patients with FH. METHODS A detailed analysis of the phenotype and genotype presented by 55 families with 13 different alterations in the LDLR was conducted. For eight of these, an extensive functional characterization was performed by flow cytometry, confocal microscopy, and reverse transcriptase polymerase chain reaction. RESULTS Carriers of neutral alterations presented a significantly lower incidence of premature cardiovascular disease, lower levels of atherogenic lipoproteins and a large number of these individuals had LDL-cholesterol values below the 75(th) percentile. presented a significantly lower incidence of premature cardiovascular disease, lower levels of atherogenic lipoproteins and a large number of these individuals had LDL-cholesterol values below the 75th percentile However, the functional study was essential to determine the pathogenicity of variants. CONCLUSION The data collected illustrate the importance of this integrated analysis for the correct assessment of patients with FH who can otherwise be misdiagnosed.
Collapse
|
41
|
Bell DA, Pang J, Burrows S, Bates TR, van Bockxmeer FM, Hooper AJ, O'Leary P, Burnett JR, Watts GF. Effectiveness of genetic cascade screening for familial hypercholesterolaemia using a centrally co-ordinated clinical service: An Australian experience. Atherosclerosis 2015; 239:93-100. [DOI: 10.1016/j.atherosclerosis.2014.12.036] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 12/18/2014] [Accepted: 12/21/2014] [Indexed: 12/13/2022]
|
42
|
Cymbron T, Mendes P, Ramos A, Raposo M, Kazachkova N, Medeiros AM, Bruges-Armas J, Bourbon M, Lima M. Familial hypercholesterolemia: Molecular characterization of possible cases from the Azores Islands (Portugal). Meta Gene 2014; 2:638-45. [PMID: 25606447 PMCID: PMC4287853 DOI: 10.1016/j.mgene.2014.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/30/2014] [Accepted: 08/15/2014] [Indexed: 01/17/2023] Open
Abstract
Familial hypercholesterolemia (FH) is an autosomal dominant disorder of the cholesterol metabolism, which constitutes a risk factor for coronary arterial disease (CAD). In the Azores Islands (Portugal), where mortality from CAD doubles its rate comparatively to the rest of the country and where a high frequency of dyslipidemia has been reported, the prevalence and distribution of FH remain unknown. The molecular characterization of a group of 33 possible cases of FH of Azorean background was undertaken in this study. A DNA array was initially used to search mutations in the LDLR, APOB and PCSK9 loci in 10 unrelated possible cases of FH. No mutations were detected in the array; after sequencing the full LDLR gene, 18 variants were identified, corresponding to two missense (c.806G > A; c.1171G > A) and sixteen synonymous alterations. Six of the synonymous variants which are consistently described in the literature as associated with altered cholesterol levels were used to build haplotypes. The most frequent haplotype corresponded to TTCGCC (45%), a “risk” haplotype, formed exclusively by alleles that were reported to increase cholesterol levels. Some of the variants detected in the full sequencing of the LDLR gene fell within the ligand-binding domain of this gene, defined by exons 2 to 6. To add information as to the role of such variants, these exons were sequenced in the remaining 23 possible FH cases. Two missense alterations (c.185C > T; c.806G > A) were found in this subset of possible FH cases. The missense alteration c.185C > T, identified in one individual, is novel for the Portuguese population. In silico analysis was not conclusive for this alteration, whose role will have to be further investigated. This study represents the first approach to the establishment of the mutational profile of FH in the Azores Islands.
Collapse
Affiliation(s)
- Teresa Cymbron
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, 9501-801 Ponta Delgada, Azores, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal
| | - Patrícia Mendes
- The Azores School of New Technologies (ENTA), 9504-540 Ponta Delgada, Azores, Portugal
| | - Amanda Ramos
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, 9501-801 Ponta Delgada, Azores, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal
| | - Mafalda Raposo
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, 9501-801 Ponta Delgada, Azores, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal
| | - Nadiya Kazachkova
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, 9501-801 Ponta Delgada, Azores, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal
| | - Ana Margarida Medeiros
- Grupo de Investigação Cardiovascular, Unidade I&D, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Dr. Ricardo Jorge, 1649-040 Lisboa, Portugal ; Centre for Biodiversity, Functional and Integrative Genomics (BioFIG), Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Jácome Bruges-Armas
- Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal ; Specialized Service of Epidemiology and Molecular Biology (SEEBMO), Hospital of Santo Espírito, 9700-049 Angra do Heroísmo, Azores, Portugal
| | - Mafalda Bourbon
- Grupo de Investigação Cardiovascular, Unidade I&D, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Dr. Ricardo Jorge, 1649-040 Lisboa, Portugal ; Centre for Biodiversity, Functional and Integrative Genomics (BioFIG), Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Manuela Lima
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, 9501-801 Ponta Delgada, Azores, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, 4150-180 Porto, Portugal
| |
Collapse
|
43
|
Medeiros AM, Alves AC, Aguiar P, Bourbon M. Cardiovascular risk assessment of dyslipidemic children: analysis of biomarkers to identify monogenic dyslipidemia. J Lipid Res 2014; 55:947-55. [PMID: 24627126 DOI: 10.1194/jlr.p043182] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The distinction between a monogenic dyslipidemia and a polygenic/environmental dyslipidemia is important for the cardiovascular risk assessment, counseling, and treatment of these patients. The present work aims to perform the cardiovascular risk assessment of dyslipidemic children to identify useful biomarkers for clinical criteria improvement in clinical settings. Main cardiovascular risk factors were analyzed in a cohort of 237 unrelated children with clinical diagnosis of familial hypercholesterolemia (FH). About 40% carried at least two cardiovascular risk factors and 37.6% had FH, presenting mutations in LDLR and APOB. FH children showed significant elevated atherogenic markers and lower concentration of antiatherogenic particles. Children without a molecular diagnosis of FH had higher levels of TGs, apoC2, apoC3, and higher frequency of BMI and overweight/obesity, suggesting that environmental factors can be the underlying cause of their hypercholesterolem≥ia. An apoB/apoA1 ratio ≥0.68 was identified as the best biomarker (area under the curve = 0.835) to differentiate FH from other dyslipidemias. The inclusion in clinical criteria of a higher cut-off point for LDL cholesterol or an apoB/apoA1 ratio ≥0.68 optimized the criteria sensitivity and specificity. The correct identification, at an early age, of all children at-risk is of great importance so that specific interventions can be implemented. apoB/apoA1 can improve the identification of FH patients.
Collapse
Affiliation(s)
- Ana Margarida Medeiros
- Unidade de Investigação & Desenvolvimento, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Dr. Ricardo Jorge, Lisboa, Portugal
| | | | | | | | | |
Collapse
|
44
|
Vishwanath R, Hemphill LC. Familial hypercholesterolemia and estimation of US patients eligible for low-density lipoprotein apheresis after maximally tolerated lipid-lowering therapy. J Clin Lipidol 2014; 8:18-28. [DOI: 10.1016/j.jacl.2013.11.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/27/2013] [Accepted: 11/01/2013] [Indexed: 10/26/2022]
|
45
|
Alves AC, Etxebarria A, Soutar AK, Martin C, Bourbon M. Novel functional APOB mutations outside LDL-binding region causing familial hypercholesterolaemia. Hum Mol Genet 2013; 23:1817-28. [DOI: 10.1093/hmg/ddt573] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
|
46
|
Espinheira MDC, Vasconcelos C, Medeiros AM, Alves AC, Bourbon M, Guerra A. Hypercholesterolemia--a disease with expression from childhood. Rev Port Cardiol 2013; 32:379-86. [PMID: 23669405 DOI: 10.1016/j.repc.2012.09.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/09/2012] [Accepted: 09/12/2012] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Hypercholesterolemia results from an alteration, genetic or acquired, in lipoprotein metabolism. Evidence that hypercholesterolemia is associated with the atherosclerotic process from childhood justifies the screening of high-risk children and initiation of therapy at preschool ages. OBJECTIVE To assess children referred for pediatric consultations due to hypercholesterolemia. METHODS Children and adolescents referred for pediatric consultations with a diagnosis of hypercholesterolemia were enrolled. Information on family history and clinical, anthropometric and biochemical parameters was recorded and, when appropriate, molecular study was performed. RESULTS A total of 168 children were assessed. Forty-six presented a familial hypercholesterolemia phenotype and in 22 of these, a mutation in the low-density lipoprotein (LDL) receptor gene was identified. The lipid profile of the group with mutations showed significantly higher values of total and non-high-density lipoprotein (HDL) cholesterol compared to the group without mutations (total cholesterol 316.5±75.9 mg/dl vs. 260.9±42,0 mg/dl; non-HDL cholesterol 268.3±72.6 mg/dl vs. 203.5±43.9 mg/dl; p<0.05). Of the total, 55 were prescribed pharmacological therapy and the others underwent diet and exercise interventions only. A greater reduction in LDL cholesterol was observed in individuals under pharmacological therapy compared to those prescribed diet and exercise only (30.3% vs. 18.1%). Drug side effects were insignificant. CONCLUSION It is possible to maintain a normal lipid profile in most individuals with familial hypercholesterolemia in order to reduce the risk of early onset of atherosclerosis, which is associated with serious cardiovascular complications from childhood.
Collapse
|
47
|
Espinheira MDC, Vasconcelos C, Medeiros AM, Alves AC, Bourbon M, Guerra A. Hypercholesterolemia – A disease with expression since childhood. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2013. [DOI: 10.1016/j.repce.2012.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
|
48
|
Spectrum of mutations and phenotypic expression in patients with autosomal dominant hypercholesterolemia identified in Italy. Atherosclerosis 2013; 227:342-8. [DOI: 10.1016/j.atherosclerosis.2013.01.007] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/03/2013] [Accepted: 01/09/2013] [Indexed: 11/19/2022]
|
49
|
In vitro functional characterization of missense mutations in the LDLR gene. Atherosclerosis 2012; 225:128-34. [DOI: 10.1016/j.atherosclerosis.2012.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 07/28/2012] [Accepted: 08/10/2012] [Indexed: 11/22/2022]
|
50
|
Ferri N. Proprotein convertase subtilisin/kexin type 9: from the discovery to the development of new therapies for cardiovascular diseases. SCIENTIFICA 2012; 2012:927352. [PMID: 24278757 PMCID: PMC3820617 DOI: 10.6064/2012/927352] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 08/28/2012] [Indexed: 06/02/2023]
Abstract
The identification of the HMG-CoA reductase inhibitors, statins, has represented a dramatic innovation of the pharmacological modulation of hypercholesterolemia and associated cardiovascular diseases. However, not all patients receiving statins achieve guideline-recommended low density lipoprotein (LDL) cholesterol goals, particularly those at high risk. There remains, therefore, an unmet medical need to develop additional well-tolerated and effective agents to lower LDL cholesterol levels. The discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9), a secretory protein that posttranscriptionally regulates levels of low density lipoprotein receptor (LDLR) by inducing its degradation, has opened a new era of pharmacological modulation of cholesterol homeostasis. This paper summarizes the current knowledge of the basic molecular mechanism underlying the regulatory effect of LDLR expression by PCSK9 obtained from in vitro cell-cultured studies and the analysis of the crystal structure of PCSK9. It also describes the epidemiological and experimental evidences of the regulatory effect of PCSK9 on LDL cholesterol levels and cardiovascular diseases and summarizes the different pharmacological approaches under development for inhibiting PCSK9 expression, processing, and the interaction with LDLR.
Collapse
Affiliation(s)
- Nicola Ferri
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milano, Italy
| |
Collapse
|