201
|
Han SM, Hwang B, Park TG, Kim DI, Rhee MY, Lee BK, Ahn YK, Cho BR, Woo J, Hur SH, Jeong JO, Park S, Jang Y, Lee MG, Bang D, Lee JH, Lee SH. Genetic testing of Korean familial hypercholesterolemia using whole-exome sequencing. PLoS One 2015; 10:e0126706. [PMID: 25962062 PMCID: PMC4427254 DOI: 10.1371/journal.pone.0126706] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 04/07/2015] [Indexed: 12/30/2022] Open
Abstract
Familial hypercholesterolemia (FH) is a genetic disorder with an increased risk of early-onset coronary artery disease. Although some clinically diagnosed FH cases are caused by mutations in LDLR, APOB, or PCSK9, mutation detection rates and profiles can vary across ethnic groups. In this study, we aimed to provide insight into the spectrum of FH-causing mutations in Koreans. Among 136 patients referred for FH, 69 who met Simon Broome criteria with definite family history were enrolled. By whole-exome sequencing (WES) analysis, we confirmed that the 3 known FH-related genes accounted for genetic causes in 23 patients (33.3%). A substantial portion of the mutations (19 of 23 patients, 82.6%) resulted from 17 mutations and 2 copy number deletions in LDLR gene. Two mutations each in the APOB and PCSK9 genes were verified. Of these anomalies, two frameshift deletions in LDLR and one mutation in PCSK9 were identified as novel causative mutations. In particular, one novel mutation and copy number deletion were validated by co-segregation in their relatives. This study confirmed the utility of genetic diagnosis of FH through WES.
Collapse
Affiliation(s)
- Soo Min Han
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Byungjin Hwang
- Department of Chemistry, Yonsei University, Seoul, Korea
| | - Tae-gun Park
- Department of Chemistry, Yonsei University, Seoul, Korea
| | - Do-Il Kim
- Cardiology Division, Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Moo-Yong Rhee
- Cardiovascular Center, Dongguk University Ilsan Hospital, Goyang, Korea
| | - Byoung-Kwon Lee
- Cardiology Division, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Young Keun Ahn
- Heart Center of Chonnam National University Hospital, Gwangju, Korea
| | - Byung Ryul Cho
- Cardiology Division, Department of Internal Medicine, Kangwon National University Hospital, Kangwon National University College of Medicine, Chunchon, Korea
| | - Jeongtaek Woo
- Endocrinology Division, Department of Internal Medicine, Kyunghee University School of Medicine, Seoul, Korea
| | - Seung-Ho Hur
- Cardiology Division, Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea
| | - Jin-Ok Jeong
- Cardiology Division, Department of Internal Medicine, School of Medicine, Chungnam National University, Chungnam National University Hospital, Daejeon, Korea
| | - Sungha Park
- Cardiology Division, Department of Internal Medicine, Severance Cardiovascular Hospital, Seoul, Korea
- Cardiovascular Research Institute and Cardiovascular Genome Center, Yonsei University Health System, Seoul, Korea
| | - Yangsoo Jang
- Cardiology Division, Department of Internal Medicine, Severance Cardiovascular Hospital, Seoul, Korea
- Cardiovascular Research Institute and Cardiovascular Genome Center, Yonsei University Health System, Seoul, Korea
| | - Min Goo Lee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Duhee Bang
- Department of Chemistry, Yonsei University, Seoul, Korea
- * E-mail: (DB); (JHL); (SHL)
| | - Ji Hyun Lee
- Department of Oral Biology, College of Dentistry, Yonsei University, Seoul, Korea
- * E-mail: (DB); (JHL); (SHL)
| | - Sang-Hak Lee
- Cardiology Division, Department of Internal Medicine, Severance Cardiovascular Hospital, Seoul, Korea
- Cardiovascular Research Institute and Cardiovascular Genome Center, Yonsei University Health System, Seoul, Korea
- * E-mail: (DB); (JHL); (SHL)
| |
Collapse
|
202
|
|
203
|
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]
|
204
|
Thormaehlen AS, Schuberth C, Won HH, Blattmann P, Joggerst-Thomalla B, Theiss S, Asselta R, Duga S, Merlini PA, Ardissino D, Lander ES, Gabriel S, Rader DJ, Peloso GM, Pepperkok R, Kathiresan S, Runz H. Systematic cell-based phenotyping of missense alleles empowers rare variant association studies: a case for LDLR and myocardial infarction. PLoS Genet 2015; 11:e1004855. [PMID: 25647241 PMCID: PMC4409815 DOI: 10.1371/journal.pgen.1004855] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 10/27/2014] [Indexed: 01/08/2023] Open
Abstract
A fundamental challenge to contemporary genetics is to distinguish rare missense alleles that disrupt protein functions from the majority of alleles neutral on protein activities. High-throughput experimental tools to securely discriminate between disruptive and non-disruptive missense alleles are currently missing. Here we establish a scalable cell-based strategy to profile the biological effects and likely disease relevance of rare missense variants in vitro. We apply this strategy to systematically characterize missense alleles in the low-density lipoprotein receptor (LDLR) gene identified through exome sequencing of 3,235 individuals and exome-chip profiling of 39,186 individuals. Our strategy reliably identifies disruptive missense alleles, and disruptive-allele carriers have higher plasma LDL-cholesterol (LDL-C). Importantly, considering experimental data refined the risk of rare LDLR allele carriers from 4.5- to 25.3-fold for high LDL-C, and from 2.1- to 20-fold for early-onset myocardial infarction. Our study generates proof-of-concept that systematic functional variant profiling may empower rare variant-association studies by orders of magnitude. Exome sequencing has proven powerful to identify protein-coding variation across the human genome, unravel the basis of monogenic diseases and discover rare alleles that confer risk for complex disease. Nevertheless, two key challenges limit its application to complex phenotypes: first, most alleles identified in a population are extremely rare; and second, most alleles are neutral on protein activities. Consequently, association tests that rely on enumerating rare alleles in cases and controls (termed rare variant association studies, RVAS) are typically underpowered, as the many neutral alleles dampen signals that arise from the few alleles that disrupt protein functions. Strategies to securely discriminate disruptive from neutral variants are immature, in particular for missense variants. Here we show that the statistical power of RVAS improves dramatically if variants are stratified according to their in vitro ascertained functions. We establish scalable technology to objectively profile the biological effects of exome-identified missense variants in the low-density lipoprotein receptor (LDLR) through systematic overexpression and complementation experiments in cells. We demonstrate that carriers of LDLR alleles, which our experiments identify as “disruptive-missense”, have higher plasma LDL-C, and that considering in vitro data may make it possible to reduce RVAS sample sizes by more than 2-fold.
Collapse
Affiliation(s)
- Aenne S. Thormaehlen
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
| | - Christian Schuberth
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
| | - Hong-Hee Won
- Center of Human Genetic Research (CHGR), Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Peter Blattmann
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
- Cell Biology/Biophysics Unit, European Molecular Biological Laboratory, Heidelberg, Germany
| | - Brigitte Joggerst-Thomalla
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
| | - Susanne Theiss
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
| | | | | | | | | | - Eric S. Lander
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Stacey Gabriel
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Daniel J. Rader
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Gina M. Peloso
- Center of Human Genetic Research (CHGR), Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Rainer Pepperkok
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
- Cell Biology/Biophysics Unit, European Molecular Biological Laboratory, Heidelberg, Germany
| | - Sekar Kathiresan
- Center of Human Genetic Research (CHGR), Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Division of Cardiology, Ospedale Niguarda, Milan, Italy
| | - Heiko Runz
- Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
- Molecular Medicine Partnership Unit (MMPU), University of Heidelberg/ EMBL, Heidelberg, Germany
- Center of Human Genetic Research (CHGR), Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
205
|
Weng SF, Kai J, Andrew Neil H, Humphries SE, Qureshi N. Improving identification of familial hypercholesterolaemia in primary care: Derivation and validation of the familial hypercholesterolaemia case ascertainment tool (FAMCAT). Atherosclerosis 2015; 238:336-43. [DOI: 10.1016/j.atherosclerosis.2014.12.034] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 11/18/2014] [Accepted: 12/09/2014] [Indexed: 02/02/2023]
|
206
|
Screening for Familial Hypercholesterolaemia: Universal or Cascade? A Critique of Current FH Recognition Strategies. CURRENT CARDIOVASCULAR RISK REPORTS 2015. [DOI: 10.1007/s12170-014-0434-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
207
|
Would raising the total cholesterol diagnostic cut-off from 7.5 mmol/L to 9.3 mmol/L improve detection rate of patients with monogenic familial hypercholesterolaemia? Atherosclerosis 2015; 239:295-8. [PMID: 25682026 PMCID: PMC4373788 DOI: 10.1016/j.atherosclerosis.2015.01.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 01/14/2015] [Accepted: 01/15/2015] [Indexed: 11/23/2022]
Abstract
A previous report suggested that 88% of individuals in the general population with total cholesterol (TC) > 9.3 mmol/L have familial hypercholesterolaemia (FH). We tested this hypothesis in a cohort of 4896 UK civil servants, mean (SD) age 44 (±6) years, using next generation sequencing to achieve a comprehensive genetic diagnosis. 25 (0.5%) participants (mean age 49.2 years) had baseline TC > 9.3 mmol/L, and overall we found an FH-causing mutation in the LDLR gene in seven (28%) subjects. The detection rate increased to 39% by excluding eight participants with triglyceride levels over 2.3 mmol/L, and reached 75% in those with TC > 10.4 mmol/L. By extrapolation, the detection rate would be ∼25% by including all participants with TC > 8.6 mmol/L (2.5 standard deviations from the mean). Based on the 1/500 FH frequency, 30% of all FH-cases in this cohort would be missed using the 9.3 mmol/L cut-off. Given that an overall detection rate of 25% is considered economically acceptable, these data suggest that a diagnostic TC cut-off of 8.6 mmol/L, rather than 9.3 mmol/L would be clinically useful for FH in the general population. 28% of sequenced UK individuals with total cholesterol >9.3 mmol/L were found to have an FH mutation using NGS. Detection rate was higher (39%) in individuals with triglycerides lower than 2.3 mmol/L. By extrapolation, a 8.6 mmol/L (2.5 SD from the mean) cholesterol cut-off may be most economically sustainable.
Collapse
|
208
|
Puttegowda B, Ali A, Ramesh B, Manjunath CN. 'Tendon xanthomas' as an indicator of premature coronary artery disease. Oxf Med Case Reports 2015; 2015:177-8. [PMID: 25988071 PMCID: PMC4369972 DOI: 10.1093/omcr/omu066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 12/26/2014] [Accepted: 12/29/2014] [Indexed: 12/02/2022] Open
Affiliation(s)
- Beeresha Puttegowda
- Sri Jayadeva Institute of Cardiovascular Science and Research , Bangalore, Karnataka , India
| | - Amjad Ali
- Sri Jayadeva Institute of Cardiovascular Science and Research , Bangalore, Karnataka , India
| | - B Ramesh
- Sri Jayadeva Institute of Cardiovascular Science and Research , Bangalore, Karnataka , India
| | | |
Collapse
|
209
|
Genetic therapies to lower cholesterol. Vascul Pharmacol 2015; 64:11-5. [DOI: 10.1016/j.vph.2014.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/05/2014] [Accepted: 12/16/2014] [Indexed: 12/11/2022]
|
210
|
Liu Y, Qiu WZ, Yang HC, Qian YC, Huang XJ, Xu ZK. Polydopamine-assisted deposition of heparin for selective adsorption of low-density lipoprotein. RSC Adv 2015. [DOI: 10.1039/c4ra16700g] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Low-density lipoprotein (LDL) is the main carrier of blood cholesterol, with elevated levels of LDL increasing the risk of atherosclerosis.
Collapse
Affiliation(s)
- Yang Liu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Wen-Ze Qiu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Hao-Cheng Yang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Yue-Cheng Qian
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Xiao-Jun Huang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Zhi-Kang Xu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| |
Collapse
|
211
|
Long-term statin treatment in children with familial hypercholesterolemia: more insight into tolerability and adherence. Paediatr Drugs 2015; 17:159-66. [PMID: 25644328 PMCID: PMC4372689 DOI: 10.1007/s40272-014-0116-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Statins are currently the preferred pharmacological therapy in individuals with familial hypercholesterolemia (FH) with the aim to prevent premature atherosclerosis. In adults, these agents have been proven to be safe and well tolerated; however, non-adherence is a significant clinical issue. OBJECTIVES In this study, we evaluated tolerability and adherence to statin therapy in young adult FH patients 10 years after this was initiated in their childhood. METHODS A questionnaire including items on medical history, adherence and reasons for discontinuation was sent to 214 young adult FH patients that initiated statin therapy at least 10 years ago. Tolerability was defined as 100% minus the percentage of patients that discontinued statin therapy due to side effects. Adherence was defined as the extent to which patients took their medication as prescribed by their physician. We labelled patients adherent if they took 80% or more of their pills in the month preceding our assessment. RESULTS Follow-up was successful in 205 (95.8%) subjects (age 18-30 years). A history of side effects was reported by 40 (19.5%) of the patients, and mainly consisted of muscle complaints and gastrointestinal symptoms. Three patients (1.5%) discontinued statin therapy because of side effects. Rhadbomyolysis or other serious adverse events were not reported. In fact, 169 (82.4%) of 205 patients remained on statin treatment and 78.7% (148 out of 188) were adherent. None of the patient characteristics were significantly associated with adherence. CONCLUSIONS Individuals with FH who started statin therapy in childhood demonstrated good adherence during ten years of treatment. Furthermore, statin therapy was well tolerated; only a small minority discontinued therapy because of side effects and the side effects that were reported were mild in nature.
Collapse
|
212
|
Medical Management of Serum Lipids and Coronary Heart Disease. Coron Artery Dis 2015. [DOI: 10.1007/978-1-4471-2828-1_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
213
|
Ragbourne SC, Crook MA. Use of lipid-lowering medications in myasthenia gravis: a case report and literature review. J Clin Lipidol 2014; 9:256-9. [PMID: 25911083 DOI: 10.1016/j.jacl.2014.12.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 12/03/2014] [Accepted: 12/08/2014] [Indexed: 11/18/2022]
Abstract
We present a patient with myasthenia gravis (MG) who developed worsening of his condition after starting ezetimibe. We review the literature concerning lipid-modifying medications and MG. The use of bile acid sequestrant agents may have a place in the lipid management of MG patients because they did not seem to cause muscle-related side effects or worsening of MG.
Collapse
Affiliation(s)
- Sophie C Ragbourne
- Department of Clinical Biochemistry, Lewisham Hospital NHS Trust, London, UK; Guy's Hospital, Southwark, London, UK
| | - Martin A Crook
- Department of Clinical Biochemistry, Lewisham Hospital NHS Trust, London, UK; Department of Metabolic Medicine, University Hospital Lewishsam, London, UK; Guy's Hospital, Southwark, London, UK; St Thomas' Hospital, Lambeth, UK; University of Greenwich, London, UK.
| |
Collapse
|
214
|
Arechavala-Gomeza V, Khoo B, Aartsma-Rus A. Splicing modulation therapy in the treatment of genetic diseases. Appl Clin Genet 2014; 7:245-52. [PMID: 25506237 PMCID: PMC4259397 DOI: 10.2147/tacg.s71506] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Antisense-mediated splicing modulation is a tool that can be exploited in several ways to provide a potential therapy for rare genetic diseases. This approach is currently being tested in clinical trials for Duchenne muscular dystrophy and spinal muscular atrophy. The present review outlines the versatility of the approach to correct cryptic splicing, modulate alternative splicing, restore the open reading frame, and induce protein knockdown, providing examples of each. Finally, we outline a possible path forward toward the clinical application of this approach for a wide variety of inherited rare diseases.
Collapse
Affiliation(s)
| | - Bernard Khoo
- Endocrinology, Division of Medicine, University College London, London, UK
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| |
Collapse
|
215
|
Canadian Cardiovascular Society Position Statement on Familial Hypercholesterolemia. Can J Cardiol 2014; 30:1471-81. [DOI: 10.1016/j.cjca.2014.09.028] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 09/22/2014] [Accepted: 09/22/2014] [Indexed: 01/13/2023] Open
|
216
|
Futema M, Shah S, Cooper JA, Li K, Whittall RA, Sharifi M, Goldberg O, Drogari E, Mollaki V, Wiegman A, Defesche J, D'Agostino MN, D'Angelo A, Rubba P, Fortunato G, Waluś-Miarka M, Hegele RA, Aderayo Bamimore M, Durst R, Leitersdorf E, Mulder MT, Roeters van Lennep JE, Sijbrands EJG, Whittaker JC, Talmud PJ, Humphries SE. Refinement of variant selection for the LDL cholesterol genetic risk score in the diagnosis of the polygenic form of clinical familial hypercholesterolemia and replication in samples from 6 countries. Clin Chem 2014; 61:231-8. [PMID: 25414277 DOI: 10.1373/clinchem.2014.231365] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Familial hypercholesterolemia (FH) is an autosomal-dominant disorder caused by mutations in 1 of 3 genes. In the 60% of patients who are mutation negative, we have recently shown that the clinical phenotype can be associated with an accumulation of common small-effect LDL cholesterol (LDL-C)-raising alleles by use of a 12-single nucleotide polymorphism (12-SNP) score. The aims of the study were to improve the selection of SNPs and replicate the results in additional samples. METHODS We used ROC curves to determine the optimum number of LDL-C SNPs. For replication analysis, we genotyped patients with a clinical diagnosis of FH from 6 countries for 6 LDL-C-associated alleles. We compared the weighted SNP score among patients with no confirmed mutation (FH/M-), those with a mutation (FH/M+), and controls from a UK population sample (WHII). RESULTS Increasing the number of SNPs to 33 did not improve the ability of the score to discriminate between FH/M- and controls, whereas sequential removal of SNPs with smaller effects/lower frequency showed that a weighted score of 6 SNPs performed as well as the 12-SNP score. Metaanalysis of the weighted 6-SNP score, on the basis of polymorphisms in CELSR2 (cadherin, EGF LAG 7-pass G-type receptor 2), APOB (apolipoprotein B), ABCG5/8 [ATP-binding cassette, sub-family G (WHITE), member 5/8], LDLR (low density lipoprotein receptor), and APOE (apolipoprotein E) loci, in the independent FH/M- cohorts showed a consistently higher score in comparison to the WHII population (P < 2.2 × 10(-16)). Modeling in individuals with a 6-SNP score in the top three-fourths of the score distribution indicated a >95% likelihood of a polygenic explanation of their increased LDL-C. CONCLUSIONS A 6-SNP LDL-C score consistently distinguishes FH/M- patients from healthy individuals. The hypercholesterolemia in 88% of mutation-negative patients is likely to have a polygenic basis.
Collapse
Affiliation(s)
- Marta Futema
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Sonia Shah
- UCL Genetics Institute, Department of Genetics, Environment and Evolution, London, University College London, UK; Current affiliation: Centre for Neurogenetics and Statistical Genomics, Queensland Brain Institute, University of Queensland, St. Lucia, Brisbane, Australia
| | - Jackie A Cooper
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - KaWah Li
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Ros A Whittall
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Mahtab Sharifi
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Olivia Goldberg
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Euridiki Drogari
- 1st Department of Pediatrics, Unit of Metabolic Diseases, Choremio Research Laboratory, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece
| | - Vasiliki Mollaki
- 1st Department of Pediatrics, Unit of Metabolic Diseases, Choremio Research Laboratory, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece
| | | | - Joep Defesche
- Department of Vascular Medicine, Academic Medical Center, Amsterdam, The Netherlands
| | - Maria N D'Agostino
- CEINGE S.C.a r.l. Advanced Biotechnology, Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Antonietta D'Angelo
- CEINGE S.C.a r.l. Advanced Biotechnology, Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Paolo Rubba
- Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Giuliana Fortunato
- CEINGE S.C.a r.l. Advanced Biotechnology, Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Małgorzata Waluś-Miarka
- Department of Metabolic Diseases and Department of Medical Didactics, Jagiellonian University Medical College, Krakow, Poland
| | | | | | - Ronen Durst
- Center for Research, Prevention and Treatment of Atherosclerosis, Department of Medicine, Cardiology Division, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
| | - Eran Leitersdorf
- Center for Research, Prevention and Treatment of Atherosclerosis, Department of Medicine, Cardiology Division, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
| | - Monique T Mulder
- Departments of Cardiology and Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Eric J G Sijbrands
- Departments of Cardiology and Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - John C Whittaker
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK; GlaxoSmithKline Quantitative Sciences, Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Philippa J Talmud
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| | - Steve E Humphries
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute of Cardiovascular Sciences, and
| |
Collapse
|
217
|
Faiz F, Nguyen LT, van Bockxmeer FM, Hooper AJ. Genetic screening to improve the diagnosis of familial hypercholesterolemia. ACTA ACUST UNITED AC 2014. [DOI: 10.2217/clp.14.32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
|
218
|
Mollaki V, Progias P, Drogari E. Familial Hypercholesterolemia in Greek children and their families: genotype-to-phenotype correlations and a reconsideration of LDLR mutation spectrum. Atherosclerosis 2014; 237:798-804. [PMID: 25463123 DOI: 10.1016/j.atherosclerosis.2014.09.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/10/2014] [Accepted: 09/23/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVE Familial Hypercholesterolemia (FH) is a common lipid metabolism disease, resulting in premature atherosclerosis, even from childhood. We aimed to define the genetic basis of FH in children and their families, to refine the spectrum of Low-Density Lipoprotein Receptor gene (LDLR) mutations and identify genotype-to-phenotype correlations in patients of Greek origin. METHODS LDLR was analyzed in 561 patients from 262 families, by whole-gene sequencing. RESULTS Children with identified LDLR mutations showed higher lipid levels compared to non-carriers. Molecular analysis identified a mutation in 53.4% of index cases. Twenty six LDLR mutations were identified, including 19 point mutations, 2 nonsense mutations, 3 splice site mutations and 2 small insertions. Amongst patients with common mutations, carriers of c.1646G > A and c.1285G > A showed higher lipid levels, whereas carriers of c.858C > A and c.81C > G showed a milder phenotype. CONCLUSIONS The spectrum of LDLR mutations in Greece is refined and expanded, with more patients analyzed by whole-gene sequencing. Although a quick screening method is feasible for the Greek population, whole-gene sequencing is essential to identify rare variants. Children with border line lipid levels and a family history of hypercholesterolemia should be considered for molecular diagnosis, since carriers of certain mutations show milder phenotypes and may be missed during clinical diagnosis.
Collapse
Affiliation(s)
- Vasiliki Mollaki
- Unit of Metabolic Diseases, Choremio Research Laboratory, 1st Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Greece.
| | - Pavlos Progias
- Unit of Metabolic Diseases, Choremio Research Laboratory, 1st Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Greece
| | - Euridiki Drogari
- Unit of Metabolic Diseases, Choremio Research Laboratory, 1st Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Greece
| |
Collapse
|
219
|
Li N, Li Q, Tian XQ, Qian HY, Yang YJ. Mipomersen is a promising therapy in the management of hypercholesterolemia: a meta-analysis of randomized controlled trials. Am J Cardiovasc Drugs 2014; 14:367-76. [PMID: 25027352 DOI: 10.1007/s40256-014-0077-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
INTRODUCTION By inhibiting apolipoprotein B (ApoB) synthesis, mipomersen can significantly reduce ApoB-containing lipoproteins in hypercholesterolemic patients. OBJECTIVE This study sought to ascertain both the extent to which mipomersen can decrease ApoB-containing lipoproteins and the safety of mipomersen therapy. METHODS Studies were identified through PubMed, CENTRAL, Embase, Clinical Trials, reviews, and reference lists of relevant papers. The efficacy endpoints were the changes in low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), ApoB, and lipoprotein (a) [Lp(a)]. The safety endpoints were the incidence of injection-site reactions, flu-like symptoms, and elevated transaminases. RESULTS Six randomized controlled trials with 444 patients were included in the analysis. Compared with the placebo group, patients who received mipomersen therapy had a significant reduction in LDL-C (33.13%), as well as a reduction in non-HDL-C (31.70%), ApoB (33.27%), and LP(a) (26.34%). Mipomersen therapy was also associated with an obvious increase in injection-site reactions with an odds ratio (OR) of 14.15, flu-like symptoms with an OR of 2.07, and alanine aminotransferase levels ≥ 3 × the upper limit of normal with an OR of 11.21. CONCLUSIONS Mipomersen therapy is effective for lowering ApoB-containing lipoproteins in patients with severe hypercholesterolemia. Future studies exploring how to minimize side effects of mipomersen therapy are needed.
Collapse
Affiliation(s)
- Na Li
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Bei Li Shi Road, Beijing, 100037, People's Republic of China
| | | | | | | | | |
Collapse
|
220
|
Khamis A, Palmen J, Lench N, Taylor A, Badmus E, Leigh S, Humphries SE. Functional analysis of four LDLR 5'UTR and promoter variants in patients with familial hypercholesterolaemia. Eur J Hum Genet 2014; 23:790-5. [PMID: 25248394 PMCID: PMC4277481 DOI: 10.1038/ejhg.2014.199] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 06/26/2014] [Accepted: 07/09/2014] [Indexed: 11/09/2022] Open
Abstract
Familial hypercholesterolaemia (FH) is an autosomal dominant inherited disease characterised by increased low-density lipoprotein cholesterol (LDL-C) levels. The functionality of four novel variants within the LDLR 5'UTR and promoter located at c.-13A>G, c.-101T>C, c.-121T>C and c.-215A>G was investigated using in silico and in vitro assays, and a systemic bioinformatics analysis of all 36 reported promoter variants are presented. Bioinformatic tools predicted that all four variants occurred in sites likely to bind transcription factors and that binding was altered by the variant allele. Luciferase assay was performed for all the variants. Compared with wild type, the c.-101T>C and c.-121T>C variants showed significantly lower mean (±SD) luciferase activity (64 ± 8 and 72 ± 8%, all P<0.001), suggesting that these variants are causal of the FH phenotype. No significant effect on gene expression was seen for the c.-13A>G or c.-215A>G variants (96 ± 15 and 100 ± 12%), suggesting these variants are not FH causing. Similar results were seen for the c.-101T>C and c.-121T>C variants in lipid-depleted serum. However, a significant reduction in luciferase activity was seen in the c.-215A>G variant in lipid-depleted serum. Electrophoretic-mobility shift assays identified allele-specific binding of liver (hepatoma) nuclear proteins to c.-121T>C and suggestive differential binding to c.-101T>C but no binding to c.-215A>G. These data highlight the importance of in vitro testing of reported LDLR promoter variants to establish their role in FH. The functional assays performed suggest that the c.-101T>C and c.-121T>C variants are pathogenic, whereas c.-13A>G variant is benign, and the status of c.-215A>G remains unclear.
Collapse
Affiliation(s)
- Amna Khamis
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London, UK
| | - Jutta Palmen
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London, UK
| | - Nick Lench
- NE Thames Regional Genetics Service, Great Ormond Street Hospital, London, UK
| | - Alison Taylor
- NE Thames Regional Genetics Service, Great Ormond Street Hospital, London, UK
| | - Ebele Badmus
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London, UK
| | - Sarah Leigh
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London, UK
| | - Steve E Humphries
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London, UK
| |
Collapse
|
221
|
Klose G, Laufs U, März W, Windler E. Familial hypercholesterolemia: developments in diagnosis and treatment. DEUTSCHES ARZTEBLATT INTERNATIONAL 2014; 111:523-9. [PMID: 25145510 PMCID: PMC4148715 DOI: 10.3238/arztebl.2014.0523] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 08/25/2013] [Accepted: 03/21/2014] [Indexed: 01/03/2023]
Abstract
BACKGROUND Familial hypercholesterolemia (FH) is a congenital disorder of lipid metabolism characterized by a marked elevation of the plasma concentration of LDL (low-density lipoprotein) cholesterol beginning in childhood and by the early onset of coronary heart disease. It is among the commonest genetic disorders, with an estimated prevalence in Germany of at least 1 per 500 persons. METHOD Review of pertinent literature retrieved by a selective search. RESULTS FH is underdiagnosed and undertreated in Germany. It is clinically diagnosed on the basis of an elevated LDL cholesterol concentration (>190 mg/dL [4.9 mmol/L]), a family history of hypercholesterolemia, and early coronary heart disease, or the demonstration of xanthomas. The gold standard of diagnosis is the identification of the underlying genetic defect, which is possible in 80% of cases and enables the identification of affected relatives of the index patient. The recommended goals of treatment, based on the results of observational studies, are to lower the LDL cholesterol concentration by at least 50% or to less than 100 mg/dL (2.6 mmol/L) (for children: <135 mg/dL [3.5 mmol/L]). The target value is lower for patients with clinically overt atherosclerosis (<70 mg/dL [1.8 mmol/L]). Statins, combined with a health-promoting lifestyle, are the treatment of choice. Lipoprotein apheresis is used in very severe cases; its therapeutic effects on clinical endpoints and its side effect profile have not yet been documented in randomized controlled trials. CONCLUSION Familial hypercholesterolemia is a common disease that can be diagnosed simply and reliably on clinical grounds and by molecular genetic testing. Timely diagnosis and appropriate treatment can lower the risk of atherosclerosis in heterozygous patients to that of the general population.
Collapse
Affiliation(s)
- Gerald Klose
- Private practice for Internal Medicine, Gastroenterology, Cardiology and Preventional Medicine: Dres. T. Beckenbauer und S. Maierhof and joint practice Dres. K. W. Spieker and I van de Loo, Bremen
| | - Ulrich Laufs
- Department of Internal Medicine III—Cardiology, Angiology and Intensive Care Medicine, Saarland University Medical Center, Homburg/Saar
| | - Winfried März
- Medical Clinic V (Nephrology, Hypertensiology, Endocrinology, Diabetology, Rheumatology), Department of Internal Medicine, Mannheim Medical Faculty, University of Heidelberg, Mannheim
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University Graz
- Synlab Academy, Synlab Services GmbH, Mannheim
| | - Eberhard Windler
- Preventive Medicine, Department of General and Interventional Cardiology, University Hospital Hamburg-Eppendorf, Hamburg
| |
Collapse
|
222
|
Vickery AW, Bell D, Garton-Smith J, Kirke AB, Pang J, Watts GF. Optimising the detection and management of familial hypercholesterolaemia: central role of primary care and its integration with specialist services. Heart Lung Circ 2014; 23:1158-64. [PMID: 25130889 DOI: 10.1016/j.hlc.2014.07.062] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 07/09/2014] [Accepted: 07/11/2014] [Indexed: 10/25/2022]
Abstract
Familial hypercholesterolaemia (FH) is the most common monogenic lipid disorder associated with premature coronary heart disease (CHD). However, the majority of people with FH are undiagnosed or undertreated. Early cholesterol lowering therapy reduces cardiovascular disease mortality in FH. Low awareness and knowledge of FH in specialty and general practice highlights the need for strategies to improve the detection and management of FH. We present an algorithm describing a multidisciplinary approach to FH detection and management. We highlight the role of primary care, and where GPs can work with preventive cardiologists to improve care of FH. Novel strategies to detect index cases with FH are presented including the community laboratory, highlighting patients at high risk of FH, and targeted FH detection through searching the general practice database. General practitioners request over 90% of LDL cholesterol measurements in the community. Once an individual with FH is detected only a small proportion of patients require specialty management with the majority of patients suitably managed in primary care. However, it is crucial to screen family members, as 50% of first-degree family members are expected to have FH due to the autosomal dominant inheritance.
Collapse
Affiliation(s)
- Alistair W Vickery
- School of Primary, Aboriginal and Rural Health Care, University of Western Australia, Crawley, Western Australia, Australia
| | - Damon Bell
- Clinical Biochemistry, PathWest Laboratory Medicine WA, Lipid Disorders Clinic, Royal Perth Hospital, University of Western Australia; Lipid Disorders Clinic, Cardiovascular Medicine, Royal Perth Hospital, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | | | - Andrew B Kirke
- The Rural Clinical School of Western Australia (Bunbury) The University of Western Australia, Bunbury WA, Australia
| | - Jing Pang
- Lipid Disorders Clinic, Cardiovascular Medicine, Royal Perth Hospital, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - Gerald F Watts
- Lipid Disorders Clinic, Cardiovascular Medicine, Royal Perth Hospital, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| |
Collapse
|
223
|
Futema M, Plagnol V, Li K, Whittall RA, Neil HAW, Seed M, Bertolini S, Calandra S, Descamps OS, Graham CA, Hegele RA, Karpe F, Durst R, Leitersdorf E, Lench N, Nair DR, Soran H, Van Bockxmeer FM, Humphries SE. Whole exome sequencing of familial hypercholesterolaemia patients negative for LDLR/APOB/PCSK9 mutations. J Med Genet 2014; 51:537-44. [PMID: 24987033 PMCID: PMC4112429 DOI: 10.1136/jmedgenet-2014-102405] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Background Familial hypercholesterolaemia (FH) is an autosomal dominant disease of lipid metabolism, which leads to early coronary heart disease. Mutations in LDLR, APOB and PCSK9 can be detected in 80% of definite FH (DFH) patients. This study aimed to identify novel FH-causing genetic variants in patients with no detectable mutation. Methods and results Exomes of 125 unrelated DFH patients were sequenced, as part of the UK10K project. First, analysis of known FH genes identified 23 LDLR and two APOB mutations, and patients with explained causes of FH were excluded from further analysis. Second, common and rare variants in genes associated with low-density lipoprotein cholesterol (LDL-C) levels in genome-wide association study (GWAS) meta-analysis were examined. There was no clear rare variant association in LDL-C GWAS hits; however, there were 29 patients with a high LDL-C SNP score suggestive of polygenic hypercholesterolaemia. Finally, a gene-based burden test for an excess of rare (frequency <0.005) or novel variants in cases versus 1926 controls was performed, with variants with an unlikely functional effect (intronic, synonymous) filtered out. Conclusions No major novel locus for FH was detected, with no gene having a functional variant in more than three patients; however, an excess of novel variants was found in 18 genes, of which the strongest candidates included CH25H and INSIG2 (p<4.3×10−4 and p<3.7×10−3, respectively). This suggests that the genetic cause of FH in these unexplained cases is likely to be very heterogeneous, which complicates the diagnostic and novel gene discovery process.
Collapse
Affiliation(s)
- Marta Futema
- British Heart Foundation Laboratories, Centre for Cardiovascular Genetics, Institute of Cardiovascular Science, the Rayne Building University College London, London, UK
| | - Vincent Plagnol
- Department of Genetics, Environment and Evolution, UCL Genetics Institute, University College London, London, UK
| | - KaWah Li
- British Heart Foundation Laboratories, Centre for Cardiovascular Genetics, Institute of Cardiovascular Science, the Rayne Building University College London, London, UK
| | - Ros A Whittall
- British Heart Foundation Laboratories, Centre for Cardiovascular Genetics, Institute of Cardiovascular Science, the Rayne Building University College London, London, UK
| | - H Andrew W Neil
- Department of Primary Care Health Sciences, NIHR School of Primary Care Research, University of Oxford, Oxford, UK
| | - Mary Seed
- Department of Cardiology, Imperial College Health Services, Charing Cross Hospital, London, UK
| | | | | | - Sebastiano Calandra
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Colin A Graham
- Queens University Belfast & Regional Genetics Centre, Belfast Health and Social Care Trust/City Hospital Belfast BT9 7AB Northern Ireland UK
| | | | - Fredrik Karpe
- OCDEM, Radcliffe Department of Medicine, University of Oxford, Churchill Hospital, Oxford, UK
| | - Ronen Durst
- Cardiology Department, Hadassah Hebrew University Medical Center, Jerusalem, Israel Department of Medicine, Center for Research, Prevention and Treatment of Atherosclerosis, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
| | - Eran Leitersdorf
- Department of Medicine, Center for Research, Prevention and Treatment of Atherosclerosis, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
| | - Nicholas Lench
- North East Thames Regional Genetics Service, Great Ormond Street Hospital for Children, London, UK
| | - Devaki R Nair
- Consultant Lipidologist and Chemical Pathologist Director SAS Laboratory for Cardiac Biomarkers, Royal Free Hospital, London, UK
| | - Handrean Soran
- Cardiovascular Trials Unit, University Department of Medicine, Central Manchester University Hospital NHS Foundation Trust, Manchester, UK
| | - Frank M Van Bockxmeer
- Division of Laboratory Medicine, Department of Biochemistry, Royal Perth Hospital, Perth, Australia
| | | | - Steve E Humphries
- British Heart Foundation Laboratories, Centre for Cardiovascular Genetics, Institute of Cardiovascular Science, the Rayne Building University College London, London, UK
| |
Collapse
|
224
|
Malhotra A, Shafiq N, Arora A, Singh M, Kumar R, Malhotra S. Dietary interventions (plant sterols, stanols, omega-3 fatty acids, soy protein and dietary fibers) for familial hypercholesterolaemia. Cochrane Database Syst Rev 2014; 2014:CD001918. [PMID: 24913720 PMCID: PMC7063855 DOI: 10.1002/14651858.cd001918.pub3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND A cholesterol-lowering diet and several other dietary interventions have been suggested as a management approach either independently or as an adjuvant to drug therapy in children and adults with familial hypercholesterolaemia (FH). However, a consensus has yet to be reached on the most appropriate dietary treatment. Plant sterols are commonly used in FH although patients may know them by other names like phytosterols or stanols. OBJECTIVES To examine whether a cholesterol-lowering diet is more effective in reducing ischaemic heart disease and lowering cholesterol than no dietary intervention in children and adults with familial hypercholesterolaemia. Further, to compare the efficacy of supplementing a cholesterol-lowering diet with either omega-3 fatty acids, soya proteins, plant sterols or plant stanols. SEARCH METHODS We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Inborn Errors of Metabolism Trials Register, which is compiled from electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (updated with each new issue of The Cochrane Library), quarterly searches of MEDLINE and the prospective handsearching of one journal - Journal of Inherited Metabolic Disease. Most recent search of the Group's Inborn Errors of Metabolism Trials Register: 22 August 2013. We also searched PubMed to 05 February 2012. SELECTION CRITERIA Randomised controlled trials, both published and unpublished, where a cholesterol-lowering diet in children and adults with familial hypercholesterolaemia has been compared to other forms of dietary treatment or to no dietary intervention were included. DATA COLLECTION AND ANALYSIS Two authors independently assessed the trial eligibility and risk of bias and one extracted the data, with independent verification of data extraction by a colleague. MAIN RESULTS In the 2014 update of the review, 15 trials have been included, with a total of 453 participants across seven comparison groups. The included trials had either a low or unclear risk of bias for most of the parameters used for risk assessment. Only short-term outcomes could be assessed due to the short duration of follow up in the included trials. None of the primary outcomes, (incidence of ischaemic heart disease, number of deaths and age at death) were evaluated in any of the included trials. No significant differences were noted for the majority of secondary outcomes for any of the planned comparisons. However, a significant difference was found for the following comparisons and outcomes: for the comparison between plant sterols and cholesterol-lowering diet (in favour of plant sterols), total cholesterol levels, mean difference 0.30 mmol/l (95% confidence interval 0.12 to 0.48); decreased serum LDL cholesterol, mean difference -0.60 mmol/l (95% CI -0.89 to -0.31). Fasting serum HDL cholesterol levels were elevated, mean difference -0.04 mmol/l (95% CI -0.11 to 0.03) and serum triglyceride concentration was reduced, mean difference -0.03 mmol/l (95% CI -0.15 to -0.09), although these changes were not statistically significant. Similarly, guar gum when given as an add on therapy to bezafibrate reduced total cholesterol and LDL levels as compared to bezafibrate alone. AUTHORS' CONCLUSIONS No conclusions can be made about the effectiveness of a cholesterol-lowering diet, or any of the other dietary interventions suggested for familial hypercholesterolaemia, for the primary outcomes: evidence and incidence of ischaemic heart disease, number of deaths and age at death,due to the lack of data on these. Large, parallel, randomised controlled trials are needed to investigate the effectiveness of a cholesterol-lowering diet and the addition of omega-3 fatty acids, plant sterols or stanols, soya protein, dietary fibers to a cholesterol-lowering diet.
Collapse
Affiliation(s)
- Anita Malhotra
- Government Medical CollegeDepartment of PhysiologyChandigarhIndia
| | - Nusrat Shafiq
- Postgraduate Institute of Medical Education and ResearchDepartment of PharmacologyChandigarhIndia160012
| | - Anjuman Arora
- Post Graduate Institute of Medical Education and ResearchDepartment of PharmacologySector‐12ChandigarhIndiaPIN‐160012
| | - Meenu Singh
- Post Graduate Institute of Medical Education and ResearchDepartment of PediatricsSector 12ChandigarhIndia160012
| | - Rajendra Kumar
- Post graduate Institute of Medical Education and ResearchDepartment of ImmunopathologySector‐12ChandigarhIndiaPIN‐160012
| | - Samir Malhotra
- Postgraduate Institute of Medical Education and ResearchDepartment of PharmacologyChandigarhIndia160012
| | | |
Collapse
|
225
|
Abstract
BACKGROUND This study evaluated the effectiveness of long-term intensive lipid-lowering therapy in children and adolescents with familial hypercholesterolaemia. METHODS The charts of 89 children and adolescents with heterozygous familial hypercholesterolaemia among ∼1000 patients treated from 1974 to 2008 were reviewed. Familial hypercholesterolaemia was defined as low-density lipoprotein cholesterol level >90th percentile in individuals with a history of familial hypercholesterolaemia. RESULTS Of the 89 patients, 51% were male; the mean age at diagnosis was 8 ± 4 years, and the mean follow-up was 13 ± 8 years. Baseline and most recent low-density lipoprotein cholesterol levels (mg/dl) under treatment were 250 ± 50 and 142 ± 49, respectively, reduced 43% from baseline (p < 0.0001). At the most recent visit, 39 patients received statin monotherapy, mainly atorvastatin or rosuvastatin, and 50 (56%) patients received combination therapy, mainly vytorin or rosuvastain/ezetimibe, 15 patients were >30 years of age, and none developed symptomatic cardiovascular disease or needed revascularisation. CONCLUSIONS Long-term statin-based therapy can reduce low-density lipoprotein cholesterol levels in most children and adolescents with heterozygous familial hypercholesterolaemia and decrease cardiovascular risk significantly.
Collapse
|
226
|
Page MM, Bell DA, Hooper AJ, Watts GF, Burnett JR. Lipoprotein apheresis and new therapies for severe familial hypercholesterolemia in adults and children. Best Pract Res Clin Endocrinol Metab 2014; 28:387-403. [PMID: 24840266 DOI: 10.1016/j.beem.2013.10.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Familial hypercholesterolemia (FH), the most common and severe monogenic form of hypercholesterolemia, is an autosomal co-dominant disease characterized by an increased plasma low density lipoprotein (LDL)-cholesterol concentration and premature coronary heart disease (CHD). The clinical phenotype depends on the gene involved and severity of mutation (or mutations) present. Patients with homozygous or compound heterozygous FH have severe hypercholesterolemia (LDL-cholesterol >13 mmol/L) due to a gene dosing effect and without treatment have accelerated atherosclerotic CHD from birth, and frequently die of CHD before age 30. Cholesterol-lowering therapies have been shown to reduce both mortality and major adverse cardiovascular events in individuals with FH. Lipoprotein apheresis concomitant with lipid-lowering therapy is the treatment of choice for homozygous FH. This article describes the rationale and role of lipoprotein apheresis in the treatment of severe FH and outlines the recent advances in new pharmacotherapies for this condition.
Collapse
Affiliation(s)
- Michael M Page
- Lipid Disorders Clinic, Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Damon A Bell
- Lipid Disorders Clinic, Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; School of Medicine & Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; School of Medicine & Pharmacology, University of Western Australia, Perth, Western Australia, Australia; School of Pathology & Laboratory Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Gerald F Watts
- Lipid Disorders Clinic, Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; School of Medicine & Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - John R Burnett
- Lipid Disorders Clinic, Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; School of Medicine & Pharmacology, University of Western Australia, Perth, Western Australia, Australia.
| |
Collapse
|
227
|
Barkas F, Liberopoulos EN, Kostapanos MS, Liamis G, Tziallas D, Elisaf M. Lipid target achievement among patients with very high and high cardiovascular risk in a lipid clinic. Angiology 2014; 66:346-53. [PMID: 24830420 DOI: 10.1177/0003319714535073] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This was a retrospective study that assessed achievement of lipid-lowering treatment targets in the setting of a University Hospital Lipid Clinic. Low-density lipoprotein cholesterol (LDL-C) goal attainment according to National Cholesterol Education Program-Adult Treatment Panel III (NCEP ATP III) and European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) guidelines was recorded in 1000 consecutive adult patients followed for ≥3 years (mean 8 years). The LDL-C targets according to the NCEP ATP III were attained by 66% and 86% of patients with "very high" (n = 477) and "high" (n = 408) cardiovascular risk, respectively. Fewer patients were within LDL-C goals according to the ESC/EAS guidelines: 25% and 42%. Overall, 92% of the patients were on statins: 67% were on statin monotherapy, while 33% were on combinations with ezetimibe (25%), ω-3 fatty acids (5%), fibrates (4%), or colesevelam (2%). Even in a specialist lipid clinic, a large proportion of patients are not at goal according to the recent ESC/EAS guidelines.
Collapse
Affiliation(s)
- Fotios Barkas
- Department of Internal Medicine, University of Ioannina Medical School, Ioannina, Greece
| | | | - Michael S Kostapanos
- Department of Internal Medicine, University of Ioannina Medical School, Ioannina, Greece
| | - George Liamis
- Department of Internal Medicine, University of Ioannina Medical School, Ioannina, Greece
| | - Dimitrios Tziallas
- Department of Internal Medicine, University of Ioannina Medical School, Ioannina, Greece
| | - Moses Elisaf
- Department of Internal Medicine, University of Ioannina Medical School, Ioannina, Greece
| |
Collapse
|
228
|
Bell DA, Garton-Smith J, Vickery A, Kirke AB, Pang J, Bates TR, Watts GF. Familial Hypercholesterolaemia in Primary Care: Knowledge and Practices among General Practitioners in Western Australia. Heart Lung Circ 2014; 23:309-13. [DOI: 10.1016/j.hlc.2013.08.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/06/2013] [Accepted: 08/11/2013] [Indexed: 10/26/2022]
|
229
|
Integrated guidance on the care of familial hypercholesterolemia from the International FH Foundation. J Clin Lipidol 2014; 8:148-72. [DOI: 10.1016/j.jacl.2014.01.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 01/04/2014] [Indexed: 12/11/2022]
|
230
|
Myśliwiec M, Walczak M, Małecka-Tendera E, Dobrzańska A, Cybulska B, Filipiak K, Mazur A, Jarosz-Chobot P, Szadkowska A, Rynkiewicz A, Chybicka A, Socha P, Brandt A, Bautembach-Minkowska J, Zdrojewski T, Limon J, Gidding SS, Banach M. Management of familial hypercholesterolemia in children and adolescents. Position paper of the Polish Lipid Expert Forum. J Clin Lipidol 2014; 8:173-80. [DOI: 10.1016/j.jacl.2014.01.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 01/03/2014] [Accepted: 01/04/2014] [Indexed: 10/25/2022]
|
231
|
Watts GF, Gidding S, Wierzbicki AS, Toth PP, Alonso R, Brown WV, Bruckert E, Defesche J, Lin KK, Livingston M, Mata P, Parhofer KG, Raal FJ, Santos RD, Sijbrands EJ, Simpson WG, Sullivan DR, Susekov AV, Tomlinson B, Wiegman A, Yamashita S, Kastelein JJ. Integrated guidance on the care of familial hypercholesterolaemia from the International FH Foundation. Int J Cardiol 2014; 171:309-25. [DOI: 10.1016/j.ijcard.2013.11.025] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 11/02/2013] [Indexed: 12/18/2022]
|
232
|
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
|
233
|
Foody JM. Familial hypercholesterolemia: an under-recognized but significant concern in cardiology practice. Clin Cardiol 2013; 37:119-25. [PMID: 24193792 DOI: 10.1002/clc.22223] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/08/2013] [Indexed: 01/14/2023] Open
Abstract
Familial hypercholesterolemia (FH) is a common disorder in which genetic mutations in at least 1 of several genes lead to significantly increased levels of lipoproteins, in particular, low-density lipoprotein cholesterol. Most commonly, mutations in the low-density lipoprotein receptor gene result in high plasma levels of apolipoprotein B-containing lipoproteins (eg, low-density lipoprotein and lipoprotein(a)). High plasma levels of lipoproteins increase the risk of cardiovascular events by as much as 20-fold if left untreated. A 2011 survey of cardiologists performed by the American College of Cardiology (ACC) suggests that there is a need for greater awareness of FH among cardiologists with regard to its prevalence and heritability, and of the risk of cardiovascular (CV) disease associated with the disorder, such as premature coronary heart disease. Given that many patients with FH may first present to CV specialists at the time of a major coronary event, it is critical that cardiologists have strategies to manage this high-risk subset of patients. This brief review responds to areas of need identified in the ACC survey and is intended to provide current information about FH and increase awareness about this disorder among cardiologists.
Collapse
Affiliation(s)
- JoAnne M Foody
- Cardiovascular Wellness Program, Brigham & Women's Hospital and Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
234
|
Cassagnol M, Ezzo D, Patel PN. New therapeutic alternatives for the management of dyslipidemia. J Pharm Pract 2013; 26:528-40. [PMID: 24142496 DOI: 10.1177/0897190013507582] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Hypercholesterolemia affects over 34 million adults in the United States and is a major cause of coronary heart disease (CHD). Conventional therapies, such as statins, have demonstrated their ability to improve clinical end points and decrease morbidity and mortality in patients with CHD. Lomitapide (Juxtapid(®)), mipomersen (Kynamro(®)), and icosapent (Vascepa(®)) are 3 novel agents approved by the US Food and Drug Administration in the past 2 years, which offer new lipid-lowering treatment options with unique pharmacology.
Collapse
Affiliation(s)
- Manouchkathe Cassagnol
- St. John's University, College of Pharmacy and Health Sciences, Department of Clinical Pharmacy Practice, Queens, New York, USA and Long Island Jewish Medical Center, Department of Pharmacy, New Hyde Park, New York, USA
| | | | | |
Collapse
|
235
|
Familial hypercholesterolaemia: a pressing issue for European health care. Atherosclerosis 2013; 231:223-6. [PMID: 24267231 DOI: 10.1016/j.atherosclerosis.2013.09.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 09/22/2013] [Indexed: 11/22/2022]
Abstract
The recent European Atherosclerosis Society (EAS) guidelines for the management of familial hypercholesterolaemia (FH) succinctly reiterate the under-diagnosis and poor management of this common genetic disorder, which is associated with greatly increased mortality from coronary heart disease (CHD), especially in young people. The prevalence of FH is thought to be between 1/500 and 1/200, and thus in Europe 1.8-4.5 million individuals have FH. In most European countries including the UK, fewer than 15% of cases have been identified to date, amounting to over 100,000 undiagnosed cases in the UK alone. There are a number of issues that have impeded the implementation of FH diagnostic and management guidelines in Europe; here, we briefly review the current situation in the UK, and propose ways to start to break down implementation barriers that may be applicable across Europe. Despite guidelines by the UK National Institute of Health and Clinical Excellence (NICE) published in 2008 that recommend genetic testing of index cases and cascade screening of their family members, and the recent NICE Quality Standards for management of FH (QS41), there has been little action towards systematic diagnosis in England despite implementation of systematic screening programmes in Scotland, Wales, Northern Ireland and in other selected countries in Europe. This is surprising because early treatment with statins provides an effective and cheap treatment that reduces mortality to near that found in the normolipidaemic population. With increasing emphasis on preventive medicine and genetic diagnosis across the medical specialties, FH is a clear example of how new genome technologies can - and should - be deployed now for the benefit of patients.
Collapse
|
236
|
Jelassi A, Najah M, Slimani A, Jguirim I, Slimane MN, Varret M. Autosomal dominant hypercholesterolemia: needs for early diagnosis and cascade screening in the tunisian population. Curr Genomics 2013; 14:25-32. [PMID: 23997648 PMCID: PMC3580777 DOI: 10.2174/138920213804999200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 11/02/2012] [Accepted: 11/05/2012] [Indexed: 11/22/2022] Open
Abstract
Autosomal dominant hypercholesterolemia (ADH) is characterized by an isolated elevation of plasmatic low-density lipoprotein (LDL), which predisposes to premature coronary artery disease (CAD) and early death. ADH is largely due to mutations in the low-density lipoprotein receptor gene (LDLR), the apolipoprotein B-100 gene (APOB), or the proprotein convertase subtilisin/kexin type 9 (PCSK9). Early diagnosis and initiation of treatment can modify the disease progression and its outcomes. Therefore, cascade screening protocol with a combination of plasmatic lipid measurements and DNA testing is used to identify relatives of index cases with a clinical diagnosis of ADH. In Tunisia, an attenuated phenotypic expression of ADH was previously reported, indicating that the establishment of a special screening protocol is necessary for this population.
Collapse
Affiliation(s)
- Awatef Jelassi
- Research Unit of Genetic and Biologic Factors of Atherosclerosis, Faculty of Medicine, Monastir; Tunisia
| | | | | | | | | | | |
Collapse
|
237
|
Ademi Z, Watts GF, Juniper A, Liew D. A systematic review of economic evaluations of the detection and treatment of familial hypercholesterolemia. Int J Cardiol 2013; 167:2391-6. [DOI: 10.1016/j.ijcard.2013.01.280] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 10/27/2012] [Accepted: 01/18/2013] [Indexed: 11/25/2022]
|
238
|
Nordestgaard BG, Chapman MJ, Humphries SE, Ginsberg HN, Masana L, Descamps OS, Wiklund O, Hegele RA, Raal FJ, Defesche JC, Wiegman A, Santos RD, Watts GF, Parhofer KG, Hovingh GK, Kovanen PT, Boileau C, Averna M, Borén J, Bruckert E, Catapano AL, Kuivenhoven JA, Pajukanta P, Ray K, Stalenhoef AFH, Stroes E, Taskinen MR, Tybjærg-Hansen A. Familial hypercholesterolaemia is underdiagnosed and undertreated in the general population: guidance for clinicians to prevent coronary heart disease: consensus statement of the European Atherosclerosis Society. Eur Heart J 2013. [PMID: 23956253 DOI: 10.1093/eurheartj.eht273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AIMS The first aim was to critically evaluate the extent to which familial hypercholesterolaemia (FH) is underdiagnosed and undertreated. The second aim was to provide guidance for screening and treatment of FH, in order to prevent coronary heart disease (CHD). METHODS AND RESULTS Of the theoretical estimated prevalence of 1/500 for heterozygous FH, <1% are diagnosed in most countries. Recently, direct screening in a Northern European general population diagnosed approximately 1/200 with heterozygous FH. All reported studies document failure to achieve recommended LDL cholesterol targets in a large proportion of individuals with FH, and up to 13-fold increased risk of CHD. Based on prevalences between 1/500 and 1/200, between 14 and 34 million individuals worldwide have FH. We recommend that children, adults, and families should be screened for FH if a person or family member presents with FH, a plasma cholesterol level in an adult ≥8 mmol/L(≥310 mg/dL) or a child ≥6 mmol/L(≥230 mg/dL), premature CHD, tendon xanthomas, or sudden premature cardiac death. In FH, low-density lipoprotein cholesterol targets are <3.5 mmol/L(<135 mg/dL) for children, <2.5 mmol/L(<100 mg/dL) for adults, and <1.8 mmol/L(<70 mg/dL) for adults with known CHD or diabetes. In addition to lifestyle and dietary counselling, treatment priorities are (i) in children, statins, ezetimibe, and bile acid binding resins, and (ii) in adults, maximal potent statin dose, ezetimibe, and bile acid binding resins. Lipoprotein apheresis can be offered in homozygotes and in treatment-resistant heterozygotes with CHD. CONCLUSION Owing to severe underdiagnosis and undertreatment of FH, there is an urgent worldwide need for diagnostic screening together with early and aggressive treatment of this extremely high-risk condition.
Collapse
Affiliation(s)
- Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, University of Copenhagen, DK-2730 Herlev, Copenhagen, Denmark
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
239
|
Nordestgaard BG, Chapman MJ, Humphries SE, Ginsberg HN, Masana L, Descamps OS, Wiklund O, Hegele RA, Raal FJ, Defesche JC, Wiegman A, Santos RD, Watts GF, Parhofer KG, Hovingh GK, Kovanen PT, Boileau C, Averna M, Borén J, Bruckert E, Catapano AL, Kuivenhoven JA, Pajukanta P, Ray K, Stalenhoef AFH, Stroes E, Taskinen MR, Tybjærg-Hansen A. Familial hypercholesterolaemia is underdiagnosed and undertreated in the general population: guidance for clinicians to prevent coronary heart disease: consensus statement of the European Atherosclerosis Society. Eur Heart J 2013; 34:3478-90a. [PMID: 23956253 PMCID: PMC3844152 DOI: 10.1093/eurheartj/eht273] [Citation(s) in RCA: 1842] [Impact Index Per Article: 167.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Aims The first aim was to critically evaluate the extent to which familial hypercholesterolaemia (FH) is underdiagnosed and undertreated. The second aim was to provide guidance for screening and treatment of FH, in order to prevent coronary heart disease (CHD). Methods and results Of the theoretical estimated prevalence of 1/500 for heterozygous FH, <1% are diagnosed in most countries. Recently, direct screening in a Northern European general population diagnosed approximately 1/200 with heterozygous FH. All reported studies document failure to achieve recommended LDL cholesterol targets in a large proportion of individuals with FH, and up to 13-fold increased risk of CHD. Based on prevalences between 1/500 and 1/200, between 14 and 34 million individuals worldwide have FH. We recommend that children, adults, and families should be screened for FH if a person or family member presents with FH, a plasma cholesterol level in an adult ≥8 mmol/L(≥310 mg/dL) or a child ≥6 mmol/L(≥230 mg/dL), premature CHD, tendon xanthomas, or sudden premature cardiac death. In FH, low-density lipoprotein cholesterol targets are <3.5 mmol/L(<135 mg/dL) for children, <2.5 mmol/L(<100 mg/dL) for adults, and <1.8 mmol/L(<70 mg/dL) for adults with known CHD or diabetes. In addition to lifestyle and dietary counselling, treatment priorities are (i) in children, statins, ezetimibe, and bile acid binding resins, and (ii) in adults, maximal potent statin dose, ezetimibe, and bile acid binding resins. Lipoprotein apheresis can be offered in homozygotes and in treatment-resistant heterozygotes with CHD. Conclusion Owing to severe underdiagnosis and undertreatment of FH, there is an urgent worldwide need for diagnostic screening together with early and aggressive treatment of this extremely high-risk condition.
Collapse
Affiliation(s)
- Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, University of Copenhagen, DK-2730 Herlev, Copenhagen, Denmark
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
240
|
Abstract
Familial hypercholesterolemia (FH) is associated with premature atherosclerotic cardiovascular diseases, and is inherited as an autosomal dominant trait. The prevalence of heterozygous FH is one in five hundred people. Owing to dysfunctional low density lipoprotein (LDL) receptors due to genetic mutations, serum low density lipoprotein-cholesterol (LDL-C) levels are considerably increased from birth. FH is clinically diagnosed by confirmation of family history and characteristic findings such as tendon xanthoma or xanthelasma. Thus, clinical concern and suspicion are important for early diagnosis of the disease. Current guidelines recommend lowering LDL-C concentration to at least 50% from baseline. Statins are shown to lower LDL-C levels with high safety, and thus, have been the drug of choice. However, it is difficult to achieve an ideal level of LDL-C with a single statin therapy in the majority of FH patients. Alternatively, lipid lowering combination therapy with the recently-introduced ezetimibe has shown more encouraging results.
Collapse
Affiliation(s)
- Yoo Ri Kim
- Department of Cardiology, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Korea
| | | |
Collapse
|
241
|
Mollaki V, Progias P, Drogari E. NovelLDLRVariants in Patients with Familial Hypercholesterolemia:In SilicoAnalysis as a Tool to Predict Pathogenic Variants in Children and Their Families. Ann Hum Genet 2013; 77:426-34. [DOI: 10.1111/ahg.12032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 05/13/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Vasiliki Mollaki
- 1st Department of Pediatrics, Laboratory of Metabolic Diseases, Choremio Research Laboratory; University of Athens Medical School, “Aghia Sophia” Children's Hospital; Athens Greece
| | - Pavlos Progias
- 1st Department of Pediatrics, Laboratory of Metabolic Diseases, Choremio Research Laboratory; University of Athens Medical School, “Aghia Sophia” Children's Hospital; Athens Greece
| | - Euridiki Drogari
- 1st Department of Pediatrics, Laboratory of Metabolic Diseases, Choremio Research Laboratory; University of Athens Medical School, “Aghia Sophia” Children's Hospital; Athens Greece
| |
Collapse
|
242
|
Farnier M, Bruckert E, Boileau C, Krempf M. Diagnostic et traitement des hypercholestérolémies familiales (HF) chez l’adulte : recommandations de la Nouvelle société française d’athérosclérose (NSFA). Presse Med 2013; 42:930-50. [DOI: 10.1016/j.lpm.2013.01.053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 01/22/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022] Open
|
243
|
ten Kate GL, ten Kate GJR, van den Oord SCH, Dedic A, Dharampal AS, Nieman K, de Feyter PJ, Sijbrands EJG, van der Steen AFW, Schinkel AFL. Carotid plaque burden as a measure of subclinical coronary artery disease in patients with heterozygous familial hypercholesterolemia. Am J Cardiol 2013; 111:1305-10. [PMID: 23411100 DOI: 10.1016/j.amjcard.2013.01.274] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 01/07/2013] [Accepted: 01/07/2013] [Indexed: 11/29/2022]
Abstract
Patients with familial hypercholesterolemia (FH) are at markedly increased risk of developing premature coronary artery disease. The objective of the present study was to evaluate the role of carotid ultrasonography as a measure of subclinical coronary artery disease in patients with FH. The present prospective study compared the presence of subclinical carotid and coronary artery disease in 67 patients with FH (mean age 55 ± 8 years, 52% men) to that in 30 controls with nonanginal chest pain (mean age 56 ± 9 years, 57% men). The carotid intima-media thickness and carotid plaque burden were assessed using B-mode ultrasonography, according to the Mannheim consensus. Coronary artery disease was assessed using computed tomographic coronary angiography. A lumen reduction >50% was considered indicative of obstructive coronary artery disease. The patients with FH and the controls had a comparable carotid intima-media thickness (0.64 vs 0.66 mm, p = 0.490), prevalence of carotid plaque (93% vs 83%, p = 0.361), and median carotid plaque score (3 vs 2, p = 0.216). Patients with FH had a significantly greater median coronary calcium score than did the controls (62 vs 5, p = 0.015). However, the prevalence of obstructive coronary artery disease was comparable (27% vs 31%, p = 0.677). No association was found between the carotid intima-media thickness and coronary artery disease. An association was found between the presence of carotid plaque and coronary artery disease in the patients with FH and the controls. The absence of carotid plaque, observed in 5 patients (7%) with FH, excluded the presence of obstructive coronary artery disease. In conclusion, the patients with FH had a high prevalence of carotid plaque and a significantly greater median coronary calcium score than did the controls. A correlation was found between carotid plaque and coronary artery disease in patients with FH; however, the presence of carotid plaque and carotid plaque burden are not reliable indicators of obstructive coronary artery disease.
Collapse
Affiliation(s)
- Gerrit L ten Kate
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | |
Collapse
|
244
|
Analysis of the frequency and spectrum of mutations recognised to cause familial hypercholesterolaemia in routine clinical practice in a UK specialist hospital lipid clinic. Atherosclerosis 2013; 229:161-8. [PMID: 23669246 PMCID: PMC3701838 DOI: 10.1016/j.atherosclerosis.2013.04.011] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 04/03/2013] [Accepted: 04/03/2013] [Indexed: 12/16/2022]
Abstract
Aim To determine the frequency and spectrum of mutations causing Familial Hypercholesterolaemia (FH) in patients attending a single UK specialist hospital lipid clinic in Oxford and to identify characteristics contributing to a high mutation detection rate. Methods 289 patients (272 probands) were screened sequentially over a 2-year period for mutations in LDLR, APOB and PCSK9 using standard molecular genetic techniques. The Simon Broome (SB) clinical diagnostic criteria were used to classify patients and a separate cohort of 409 FH patients was used for replication. Results An FH-causing mutation was found in 101 unrelated patients (LDLR = 54 different mutations, APOB p.(Arg3527Gln) = 10, PCSK9 p.(Asp374Tyr) = 0). In the 60 SB Definite FH patients the mutation detection rate was 73% while in the 142 with Possible FH the rate was significantly lower (27%, p < 0.0001), but similar (14%, p = 0.06) to the 70 in whom there was insufficient data to make a clinical diagnosis. The mutation detection rate varied significantly (p = 9.83 × 10−5) by untreated total cholesterol (TC) levels (25% in those <8.1 mmol/l and 74% in those >10.0 mmol/l), and by triglyceride levels (20% in those >2.16 mmol/l and 60% in those <1.0 mmol/l (p = 0.0005)), with both effects confirmed in the replication sample (p for trend = 0.0001 and p = 1.8 × 10−6 respectively). There was no difference in the specificity or sensitivity of the SB criteria versus the Dutch Lipid Clinic Network score in identifying mutation carriers (AROC respectively 0.73 and 0.72, p = 0.68). Conclusions In this genetically heterogeneous cohort of FH patients the mutation detection rate was significantly dependent on pre-treatment TC and triglyceride levels. 54 different LDLR mutations found in a cohort of 272 FH probands. The cohort was found to be genetically heterogeneous with no specific FH mutation. Mutation detection rate was highly dependent on pre-treatment TC and TG levels. No difference in specificity/sensitivity between 2 clinical FH diagnosis approaches. Inadequate LDL-C reduction marks the need for more effective lipid-lowering therapy.
Collapse
|
245
|
Talmud PJ, Shah S, Whittall R, Futema M, Howard P, Cooper JA, Harrison SC, Li K, Drenos F, Karpe F, Neil HAW, Descamps OS, Langenberg C, Lench N, Kivimaki M, Whittaker J, Hingorani AD, Kumari M, Humphries SE. Use of low-density lipoprotein cholesterol gene score to distinguish patients with polygenic and monogenic familial hypercholesterolaemia: a case-control study. Lancet 2013; 381:1293-301. [PMID: 23433573 DOI: 10.1016/s0140-6736(12)62127-8] [Citation(s) in RCA: 421] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Familial hypercholesterolaemia is a common autosomal-dominant disorder caused by mutations in three known genes. DNA-based cascade testing is recommended by UK guidelines to identify affected relatives; however, about 60% of patients are mutation-negative. We assessed the hypothesis that familial hypercholesterolaemia can also be caused by an accumulation of common small-effect LDL-C-raising alleles. METHODS In November, 2011, we assembled a sample of patients with familial hypercholesterolaemia from three UK-based sources and compared them with a healthy control sample from the UK Whitehall II (WHII) study. We also studied patients from a Belgian lipid clinic (Hôpital de Jolimont, Haine St-Paul, Belgium) for validation analyses. We genotyped participants for 12 common LDL-C-raising alleles identified by the Global Lipid Genetics Consortium and constructed a weighted LDL-C-raising gene score. We compared the gene score distribution among patients with familial hypercholesterolaemia with no confirmed mutation, those with an identified mutation, and controls from WHII. FINDINGS We recruited 321 mutation-negative UK patients (451 Belgian), 319 mutation-positive UK patients (273 Belgian), and 3020 controls from WHII. The mean weighted LDL-C gene score of the WHII participants (0.90 [SD 0.23]) was strongly associated with LDL-C concentration (p=1.4 x 10(-77); R(2)=0.11). Mutation-negative UK patients had a significantly higher mean weighted LDL-C score (1.0 [SD 0.21]) than did WHII controls (p=4.5 x 10(-16)), as did the mutation-negative Belgian patients (0.99 [0.19]; p=5.2 x 10(-20)). The score was also higher in UK (0.95 [0.20]; p=1.6 x 10(-5)) and Belgian (0.92 [0.20]; p=0.04) mutation-positive patients than in WHII controls. 167 (52%) of 321 mutation-negative UK patients had a score within the top three deciles of the WHII weighted LDL-C gene score distribution, and only 35 (11%) fell within the lowest three deciles. INTERPRETATION In a substantial proportion of patients with familial hypercholesterolaemia without a known mutation, their raised LDL-C concentrations might have a polygenic cause, which could compromise the efficiency of cascade testing. In patients with a detected mutation, a substantial polygenic contribution might add to the variable penetrance of the disease. FUNDING British Heart Foundation, Pfizer, AstraZeneca, Schering-Plough, National Institute for Health Research, Medical Research Council, Health and Safety Executive, Department of Health, National Heart Lung and Blood Institute, National Institute on Aging, Agency for Health Care Policy Research, John D and Catherine T MacArthur Foundation Research Networks on Successful Midlife Development and Socio-economic Status and Health, Unilever, and Departments of Health and Trade and Industry.
Collapse
Affiliation(s)
- Philippa J Talmud
- Centre for Cardiovascular Genetics, Institute of Cardiovascular Science, University College London, London, UK
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
246
|
Martin AC, Coakley J, Forbes DA, Sullivan DR, Watts GF. Familial hypercholesterolaemia in children and adolescents: a new paediatric model of care. J Paediatr Child Health 2013; 49:E263-72. [PMID: 23252991 DOI: 10.1111/jpc.12036] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/26/2012] [Indexed: 01/31/2023]
Abstract
Familial hypercholesterolaemia (FH) is a common genetic disorder affecting more than 8000 children and adolescents throughout Australia. It results in marked elevation in plasma low-density lipoprotein cholesterol levels from birth that predisposes individuals to premature coronary heart disease in adult life. The majority of children and adolescents with FH are undiagnosed, as symptoms and signs only develop after decades of hypercholesterolaemia. Cascade screening of family members after detecting FH in an index case is an effective approach that allows the diagnosis of FH to be made in the young, before significant atherosclerosis develops. With the availability of effective therapies, mainly statins, paediatricians are ideally placed to improve the outcomes of this disorder by detecting and managing hypercholesterolaemia in childhood, thereby preventing premature coronary artery disease. We describe a new paediatric model of care for FH.
Collapse
Affiliation(s)
- Andrew C Martin
- Department of Paediatric and Adolescent Medicine, Princess Margaret Hospital for Children, Perth,Western Australia, Australia.
| | | | | | | | | |
Collapse
|
247
|
ten Kate GJR, Neefjes LA, Dedic A, Nieman K, Langendonk JG, Galema-Boers AJ, Roeters van Lennep J, Moelker A, Krestin GP, Sijbrands EJ, de Feyter PJ. The effect of LDLR-negative genotype on CT coronary atherosclerosis in asymptomatic statin treated patients with heterozygous familial hypercholesterolemia. Atherosclerosis 2013; 227:334-41. [DOI: 10.1016/j.atherosclerosis.2012.12.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 12/11/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
|
248
|
Cohen JC. Emerging LDL therapies: Using human genetics to discover new therapeutic targets for plasma lipids. J Clin Lipidol 2013; 7:S1-5. [PMID: 23642322 DOI: 10.1016/j.jacl.2013.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 03/18/2013] [Accepted: 03/18/2013] [Indexed: 11/25/2022]
Abstract
In humans, genetic variation occurs through different types of alleles that vary in frequency and severity of effect. Mendelian mutations, such as those in the low-density lipoprotein (LDL) receptor (LDLR) that result in familial hypercholesterolemia, are rare and have powerful phenotypic effects. Conversely, alleles that are common in the population (such that homozygotes for the minor allele are present even in modest sample sizes) typically have very modest phenotypic effects. In the middle of the spectrum are "Goldilocks" alleles such as mutations in the gene for proprotein convertase subtilisin/kexin type 9 (PCSK9). Loss-of-function mutations in PCSK9 result in significantly decreased LDL-cholesterol levels and a disproportionately large reduction in coronary heart disease risk by reducing the exposure to LDL-cholesterol throughout life. Several agents to inhibit PCSK9 are currently in development, demonstrating the potential utility of translating genetics into clinical therapeutics. To date, most investigations aimed at identifying the genes responsible for hypercholesterolemia have used linkage analysis, which requires samples collected from multiple families with defects in the same gene, or common variant analysis which requires thousands of samples from the population. However, case studies have shown that with advances in whole genome sequencing or exome sequencing (targeted exome capture), the process of discovering causal genetic mutations can be significantly streamlined. Astute clinical observation of individual patients and their families with atypical lipid profiles, followed by sequencing of the affected individual, has the potential to lead to important findings regarding the genetic mutations that cause lipid abnormalities.
Collapse
Affiliation(s)
- Jonathan C Cohen
- Center for Human Nutrition, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
| |
Collapse
|
249
|
Ahmed W, Whittall R, Riaz M, Ajmal M, Sadeque A, Ayub H, Qamar R, Humphries SE. The genetic spectrum of familial hypercholesterolemia in Pakistan. Clin Chim Acta 2013; 421:219-25. [PMID: 23535506 PMCID: PMC3701840 DOI: 10.1016/j.cca.2013.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 03/13/2013] [Indexed: 12/28/2022]
Abstract
Background Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by mutations in the genes coding for the low density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type-9 (PCSK9) or apo-lipoprotein B-100 (APOB). The aim of the present work was to determine the genetic basis of dyslipidemia in 11 unrelated Pakistani families. Methods High resolution melting (HRM), sequencing and restriction fragment length polymorphism (RFLP). Results Probands were screened for the promoter and all coding regions, including intron/exon boundaries, of LDLR and PCSK9 and part of exon 26 of APOB including p.(R3527Q). Two families were identified with previously unreported LDLR mutations (c.1019_1020delinsTG, p.(C340L) and c.1634G>A, p.(G545E)). Both probands had tendon xanthomas or xanthelasma and/or a history of cardiovascular disease. Co-segregation with hypercholesterolemia was demonstrated in both families. In silico studies predicted these variations to be damaging. In two families, novel PCSK9 variations were identified (exon2; c.314G > A, p.(R105Q) and exon3; c.464C>T, p.(P155L)). In silico studies suggested both were likely to be damaging, and family members carrying the p.(105Q) allele had lower total cholesterol levels, suggesting this is a loss-of-function mutation. For c.464C>T p.(P155L) the small number of relatives available precluded any strong inference. Conclusion This report brings to seven the number of different LDLR mutations reported in FH patients from Pakistan and, as expected in this heterogeneous population, no common LDLR mutation has been identified. We examined the LDLR/PCSK9 genes in patients with FH from Pakistan. Two novel LDLR mutations both showed co-segregation with hypercholesterolemia. Two novel PCSK9 variations were found one of which was a loss of function mutation. This brings to 7 the number of molecular causes of FH in patients from Pakistan.
Collapse
Affiliation(s)
- Waqas Ahmed
- COMSATS Institute of Information Technology, Islamabad, Pakistan
| | | | | | | | | | | | | | | |
Collapse
|
250
|
Futema M, Plagnol V, Whittall RA, Neil HAW, Humphries SE. Use of targeted exome sequencing as a diagnostic tool for Familial Hypercholesterolaemia. J Med Genet 2013; 49:644-9. [PMID: 23054246 PMCID: PMC3475071 DOI: 10.1136/jmedgenet-2012-101189] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Familial Hypercholesterolaemia (FH) is an autosomal dominant disease, caused by mutations in LDLR, APOB or PCSK9, which results in high levels of LDL-cholesterol (LDL-C) leading to early coronary heart disease. An autosomal recessive form of FH is also known, due to homozygous mutations in LDLRAP1. This study assessed the utility of an exome capture method and deep sequencing in FH diagnosis. METHODS Exomes of 48 definite FH patients, with no mutation detected by current methods, were captured by Agilent Human All Exon 50Mb assay and sequenced on the Illumina HiSeq 2000 platform. Variants were called by GATK and SAMtools. RESULTS The mean coverage of FH genes varied considerably (PCSK9=23x, LDLRAP1=36x, LDLR=56x and APOB=93x). Exome sequencing detected 17 LDLR mutations, including three copy number variants, two APOB mutations, missed by the standard techniques, two LDLR novel variants likely to be FH-causing, and five APOB variants of uncertain effect. Two variants called in PCSK9 were not confirmed by Sanger sequencing. One heterozygous mutation was found in LDLRAP1. CONCLUSIONS High-throughput DNA sequencing demonstrated its efficiency in well-covered DNA regions, in particular LDLR. This highly automated technology is proving to be effective for heterogeneous diseases and may soon replace laborious conventional methods. However, the poor coverage of gene promoters and repetitive, or GC-rich sequences, remains problematic, and validation of all identified variants is currently required.
Collapse
Affiliation(s)
- Marta Futema
- Centre for Cardiovascular Genetics, British Heart Foundation Laboratories, Institute Cardiovascular Science, University College London Medicine School, London WC1E 6JF, UK
| | | | | | | | | | | | | |
Collapse
|