A Comprehensive Analysis of Genomics and Metagenomics in a Heterozygote Familial Hypercholesterolemia Family

Familial hypercholesterolemia (FH) is an inherited rare disease leading to markedly elevated low-density lipoprotein cholesterol (LDL-C) levels and increased risk for cardiovascular event. Gut microbiota has been implicated as a pivotal contributing factor in hyperlipidemia, however, its role in FH remains elusive. We performed whole-exome and metagenomics sequencing on a family with 22 members in which myocardial infarctions occurred at a young age with unclear etiology. We confirmed the missense mutation of LDLR c.1723C>T accounted for the abnormal cholesterol metabolism in the family through co-segregation analysis. In addition, Prevotella dentalis was found elevated and strongly associated with LDL-C level in FH family members with mutation of LDLR c.1723C>T compared to unaffected members with hyperlipidemia. Overall, our work suggests that whole-exome sequencing can facilitate identification of disease-causing variants and enable preventive treatment of FH. Our metagenomics analysis provides early insights into potential contributions of host-microbe interactions in genetic and common hypercholesterolemia.

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Abstract 16143: A Novel Clinical Prediction Model for Familial Hypercholesterolemia: Implementation of a Statin-correction Calculator to Enhance Diagnostic Yield

Circulation ◽

10.1161/circ.142.suppl_3.16143 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Zahara A Kanji ◽

Mohammad S Sheikh ◽

Daniel Antwi-Amoabeng ◽

Bryce H Beutler ◽

Nageshwara Gullapalli ◽

...

Keyword(s):

Statin Therapy ◽

Familial Hypercholesterolemia ◽

Diagnostic Yield ◽

Genetic Disorder ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Clinical Criteria ◽

Gene Testing ◽

Whole Exome ◽

Pre Treatment

Introduction: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder. Individuals with FH have a 22-fold greater risk of early-onset cardiovascular disease as compared to the general population. Early identification of patients with FH is essential to prevent cardiovascular events. Diagnosis may be challenging however for individuals with underlying FH who are already receiving statin therapy, as criteria for FH rely on pre-treatment low-density lipoprotein (LDL) levels. We calculated pre-treatment LDL levels utilizing prior published literature by adjusting for serum LDL levels in patients receiving statins. This increased the diagnostic yield for gene-positive FH. Hypothesis: Integration of statin-correction calculator with the Dutch Lipid Clinical Criteria (DLCC) and Simon Broome Criteria (SBC) for FH will increase sensitivity to identify gene-positive FH. Methods: 29,797 participants enrolled in the Healthy Nevada Project underwent whole-exome gene testing. 126 had a FH variant; 37 of these participants were on statin therapy. A statin-correction calculator was utilized to predict patients' pre-treatment LDL levels. The likelihood of FH was assessed based on two versions of the DLCC and SBC: the standard versions and enhanced versions with integration of the statin-correction calculator (eDLCC and eSBC). The McNemar test was used to compare the sensitivity of DLCC and SBC with eDLCC and eSBC, respectively, in identifying gene-positive FH. Results: By adjusting LDL levels for statin usage, 70.24% and 24.32% of participants with a negative diagnosis of FH were reclassified to positive using eDLCC and eSBC (p=0.001 and 0.008, respectively). Conclusions: Integration of statin-correction calculator to correct LDL increases diagnostic yield for clinical FH.

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Degradation of cationized low density lipoprotein and regulation of cholesterol metabolism in homozygous familial hypercholesterolemia fibroblasts.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.73.9.3178 ◽

1976 ◽

Vol 73 (9) ◽

pp. 3178-3182 ◽

Cited By ~ 609

Author(s):

S. K. Basu ◽

J. L. Goldstein ◽

G. W. Anderson ◽

M. S. Brown

Keyword(s):

Familial Hypercholesterolemia ◽

Cholesterol Metabolism ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Low Density ◽

Homozygous Familial Hypercholesterolemia

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Large-Scale Screening for Monogenic and Clinically Defined Familial Hypercholesterolemia in Iceland

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvbaha.120.315904 ◽

2021 ◽

Vol 41 (10) ◽

pp. 2616-2628 ◽

Cited By ~ 1

Author(s):

Eythór Björnsson ◽

Guðmundur Thorgeirsson ◽

Anna Helgadóttir ◽

Guðmar Thorleifsson ◽

Garðar Sveinbjörnsson ◽

...

Keyword(s):

Familial Hypercholesterolemia ◽

Large Scale ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Causative Mutation ◽

Monogenic Disease ◽

Lipid Clinic ◽

Increased Risk ◽

Cholesterol Guidelines ◽

European Society Of Cardiology

Objective: Familial hypercholesterolemia (FH) is traditionally defined as a monogenic disease characterized by severely elevated LDL-C (low-density lipoprotein cholesterol) levels. In practice, FH is commonly a clinical diagnosis without confirmation of a causative mutation. In this study, we sought to characterize and compare monogenic and clinically defined FH in a large sample of Icelanders. Approach and Results: We whole-genome sequenced 49 962 Icelanders and imputed the identified variants into an overall sample of 166 281 chip-genotyped Icelanders. We identified 20 FH mutations in LDLR , APOB , and PCSK9 with combined prevalence of 1 in 836. Monogenic FH was associated with severely elevated LDL-C levels and increased risk of premature coronary disease, aortic valve stenosis, and high burden of coronary atherosclerosis. We used a modified version of the Dutch Lipid Clinic Network criteria to screen for the clinical FH phenotype among living adult participants (N=79 058). Clinical FH was found in 2.2% of participants, of whom only 5.2% had monogenic FH. Mutation-negative clinical FH has a strong polygenic basis. Both individuals with monogenic FH and individuals with mutation-negative clinical FH were markedly undertreated with cholesterol-lowering medications and only a minority attained an LDL-C target of <2.6 mmol/L (<100 mg/dL; 11.0% and 24.9%, respectively) or <1.8 mmol/L (<70 mg/dL; 0.0% and 5.2%, respectively), as recommended for primary prevention by European Society of Cardiology/European Atherosclerosis Society cholesterol guidelines. Conclusions: Clinically defined FH is a relatively common phenotype that is explained by monogenic FH in only a minority of cases. Both monogenic and clinical FH confer high cardiovascular risk but are markedly undertreated.

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Microfluidic Amplification as a Tool for Massive Parallel Sequencing of the Familial Hypercholesterolemia Genes

Clinical Chemistry ◽

10.1373/clinchem.2011.173963 ◽

2012 ◽

Vol 58 (4) ◽

pp. 717-724 ◽

Cited By ~ 26

Author(s):

Silke Hollants ◽

Egbert J W Redeker ◽

Gert Matthijs

Keyword(s):

Familial Hypercholesterolemia ◽

Cholesterol Metabolism ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Massive Parallel Sequencing ◽

Autosomal Dominant Disorder ◽

Parallel Sequencing ◽

Mutation Scanning ◽

Variant Frequency ◽

Positive Controls

Abstract BACKGROUND Familial hypercholesterolemia (FH) is an autosomal dominant disorder that affects cholesterol metabolism and is an important risk factor for heart disease. Three different genes were causally linked to this disorder: LDLR (low density lipoprotein receptor), APOB [apolipoprotein B (including Ag(x) antigen)], and PCSK9 (proprotein convertase subtilisin/kexin type 9). We evaluated a new amplicon preparation tool for resequencing these genes on next generation sequencing (NGS) platforms. METHODS For the 3 genes, 38 primer pairs were designed and loaded on the Fluidigm Access Array, a microfluidic array in which a PCR was performed. We amplified 144 DNA samples (73 positive controls and 71 patient samples) and performed 3 sequencing runs on a GS FLX Titanium system from Roche 454, using pyrosequencing. Data were analyzed with the SeqNext module of the Sequence Pilot software. RESULT From the 38 amplicons, 37 were amplified successfully, without any further optimization. Sequencing resulted in a mean coverage of the individual amplicons of 71-fold, 74-fold, and 117-fold for the 3 runs, respectively. In the positive controls, all known mutations were identified. In 29% of the patient samples, a pathogenic point mutation or small deletion/insertion was found. Large rearrangements were not detectable with NGS, but were picked up by multiplex ligation-dependent probe amplification. CONCLUSIONS Combining a microfluidic amplification system with massive parallel sequencing is an effective method for mutation scanning in FH patients, which can be implemented in diagnostics. For data analysis, we propose a minimum variant frequency threshold of 20% and a minimum coverage of 25-fold.

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Identifying Markers of Cardiovascular Event-Free Survival in Familial Hypercholesterolemia

Journal of Clinical Medicine ◽

10.3390/jcm10010064 ◽

2020 ◽

Vol 10 (1) ◽

pp. 64

Author(s):

Etienne Khoury ◽

Diane Brisson ◽

Nathalie Roy ◽

Gérald Tremblay ◽

Daniel Gaudet

Keyword(s):

Familial Hypercholesterolemia ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Elderly Subjects ◽

Atherosclerotic Cardiovascular Disease ◽

Cvd Risk ◽

Free Survival ◽

Logistic Regression Models ◽

Female Sex ◽

Increased Risk

Familial hypercholesterolemia (FH) is an autosomal dominant trait characterized by elevated low-density lipoprotein-cholesterol (LDL-C) concentrations appearing at birth and is associated with increased risk of premature atherosclerotic cardiovascular disease (CVD). However, in some cases, FH subjects over 70 years of age have surprisingly never experienced any CVD symptoms throughout their entire lives. The objective of this study consists of identifying biological and environmental markers acting as cardioprotective factors and associated with unexpected survival in FH. Upon age and reported cardiovascular events (CVE) stratification, we identified a total of 458 French–Canadian FH subjects with premature reported CVE, and 1297 young adults as well as 24 elderly subjects (≥70 years) who have never reported CVE requiring hospitalization. Logistic regression models were used to depict cardioprotective markers among FH survivors (≥70 years). Regression analyses of the FH cohort showed that female sex (odds ratio (OR) = 12.92 (4.23–39.46); p < 0.0001), high levels of high-density lipoprotein (HDL)-C (OR = 6.76 (2.43–18.79); p = 0.0002) and elevated concentrations of adiponectin (OR = 71.40 (5.20–980.47); p = 0.001) were significant contributory factors in reducing FH-related CVD risk. Notably, female (OR = 11.45 (1.25–105.98); p = 0.031) and high HDL-C (OR = 9.78 (1.75–54.67); p = 0.009) were shown to be significant covariates associated with survival in FH. Non-smoking (OR = 11.73 (4.36–31.56); p < 0.0001) was also identified as an environmental factor associated with CVE-free survival. Based on this configured model of premature CVE occurrence, these results demonstrated that, beyond LDL-C levels, female sex, high HDL-C, elevated adiponectin and non-smoking are important markers that contribute to a reduced risk of CVD and CVE-free survival in FH.

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Multiplex Protein Biomarker Profiling in Patients with Familial Hypercholesterolemia

Genes ◽

10.3390/genes12101599 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1599

Author(s):

Dana Dlouha ◽

Milan Blaha ◽

Eva Rohlova ◽

Jaroslav A. Hubacek ◽

Vera Lanska ◽

...

Keyword(s):

Familial Hypercholesterolemia ◽

Plasma Proteins ◽

Cholesterol Metabolism ◽

Wide Spectrum ◽

Combined Therapy ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

High Plasma ◽

Protein Biomarkers ◽

Autosomal Dominant Disorder

Familial hypercholesterolemia (FH), is an autosomal dominant disorder caused by mutations in the LDLR, APOB, PCSK9, and APOE genes and is characterized by high plasma levels of total and low-density lipoprotein (LDL) cholesterol. Our study aimed to analyze the influences of two different therapies on a wide spectrum of plasma protein biomarkers of cardiovascular diseases. Plasma from FH patients under hypolipidemic therapy (N = 18; men = 8, age 55.4 ± 13.1 years) and patients under combined long-term LDL apheresis/hypolipidemic therapy (N = 14; men = 7; age 58.0 ± 13.6 years) were analyzed in our study. We measured a profile of 184 cardiovascular disease (CVD) associated proteins using a proximity extension assay (PEA). Hypolipidemic therapy significantly (all p < 0.01) influenced 10 plasma proteins (TM, DKK1, CCL3, CD4, PDGF subunit B, AGRP, IL18, THPO, and LOX1 decreased; ST2 increased). Under combined apheresis/hypolipidemic treatment, 18 plasma proteins (LDLR, PCSK9, MMP-3, GDF2, CTRC, SORT1, VEGFD, IL27, CCL24, and KIM1 decreased; OPN, COL1A1, KLK6, IL4RA, PLC, TNFR1, GLO1, and PTX3 increased) were significantly affected (all p < 0.006). Hypolipidemic treatment mainly affected biomarkers involved in vascular endothelial maintenance. Combined therapy influenced proteins that participate in cholesterol metabolism and inflammation.

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Clinical implications and outcomes of the ORION Phase III trials

Future Cardiology ◽

10.2217/fca-2020-0150 ◽

2020 ◽

Author(s):

Julia Brandts ◽

Kausik K Ray

Keyword(s):

Familial Hypercholesterolemia ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Phase Iii ◽

Atherosclerotic Cardiovascular Disease ◽

Low Density Lipoprotein Cholesterol ◽

Clinical Safety ◽

Phase Iii Trials ◽

Phase Ii And Iii ◽

Ongoing Phase

Inclisiran is a siRNA inhibiting hepatic PCSK9 synthesis. As a first-in-class therapy, inclisiran has been assessed within the ORION trial program for its low-density lipoprotein cholesterol (LDL-C) lowering efficacy and clinical safety. Phase II and III trials have shown that inclisiran lowers LDL-C by about 50% with an infrequent dosing schedule in patients with established atherosclerotic cardiovascular disease and those at high risk, including patients with heterozygous familial hypercholesterolemia. Ongoing Phase III trials will provide evidence on longer-term safety and effectiveness, and inclisiran’s efficacy in patients with homozygous familial hypercholesterolemia. Furthermore, the ORION-4 trial will assess inclisiran’s impact on cardiovascular outcomes.

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