OBJECTIVE: To investigate the gene detection results of 2 patients with familial hypercholesterolemia (FH) caused by complex heterozygous variation, and to clarify the relationship between clinical manifestations and gene variation. METHODS: Two patients (patient 1 and 2) with FH who visited Beijing Anzhen Hospital Affiliated to Capital Medical University in 2018 were selected as research subjects. A retrospective study method was used to collect clinical and family history data of the two patients. And 2 mL of peripheral venous blood from each of the two patients was collected, and genomic DNA extraction was performed on the blood samples. Sanger sequencing was used to validate the variant sites of the two patients detected by whole-exome sequencing (WES). Pathogenicity of variants was classified based on the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Classification of Genetic Variants (hereinafter referred to as the "ACMG Guidelines"), and the impact of variant was analyzed using multiple bioinformatics tools including SIFT, PolyPhen-2, and SWISS-MODEL. This study has been approved by Beijing Anzhen Hospital Affiliated to Capital Medical University (Ethics No. 2024215X). RESULTS: Patient 1 initially presented with early-onset coronary heart disease, with initial lipid levels of serum total cholesterol (TC) 9.86 mmol/L (normal reference value: 3.10~5.20 mmol/L) and serum low-density lipoprotein cholesterol (LDL-C) 8.37 mmol/L (normal reference value: 1.27~3.12 mmol/L) on admission. Patient 1 initially underwent treatment with rosuvastatin combined with ezetimibe for one month, but the lipid-lowering effect was not significant. The lipid-lowering therapy was then adjusted to atorvastatin combined with ezetimibe and probucol. After one year of treatment, the patient developed paroxysmal chest pain symptoms. A follow-up lipid profile showed a serum TC level of 4.50 mmol/L and a LDL-C level of 3.55 mmol/L. The lipid-lowering regimen was continued, and the serum LDL-C levels were maintained between 2.65 and 3.66 mmol/L. Patient 2 was found to have an abnormally high blood lipid level and carotid artery hardening during physical examination, with an initial blood lipid level of serum TC 11.82 mmol/L and serum LDL-C 9.63 mmol/L. After receiving rosuvastatain therapy, the lipid-lowering effect was significant. WES revealed that patient 1 carried the heterozygous variants c.1871_1873del(p.Ile624del) and c.1747C>T (p.His583Tyr) in the LDLR gene (NM_000527.4), while patient 2 carried the heterozygous variants c.1747C>T (p.His583Tyr) in the LDLR gene and c.6936_6937inv (p.Ile2313Val) in the APOB gene (NM_000384). According to the ACMG Guidelines, the LDLR gene c.1747C>T (p.His583Tyr) was classified as a pathogenic variant (PS3+PM1+PM2_supporting+PM5+PP2+PP3), and c.1871_1873del (p.Ile624del) was classified as a pathogenic variant (PS3+PS4+PM2_supporting+PM1+PM4); the APOB gene c.6936_6937inv (p.Ile2313Val) was classified as a variant of uncertain clinical significance (PM2_supporting BP4). CONCLUSION Patients 1 and 2 in this study were patients with complex heterozygous variant FH, and their genotypic differences may be related to the differences in clinical serum LDL-C levels and the efficacy of hypolipidemic agents.
Humans ; Hyperlipoproteinemia Type II/drug therapy* ; Male ; Female ; Heterozygote ; Adult ; Middle Aged ; Receptors, LDL/genetics* ; Retrospective Studies ; Mutation ; Exome Sequencing

Objective: To investigate the impact of orthotopic liver transplantation on serum lipid and growing development in patients with homozygous (HoFH) or compound heterozygotes (cHeFH) familial hypercholesterolemia. Methods: Patients who were treated in Peking Union Medical College Hospital from August 2019 to August 2021, entered the rare disease database and underwent liver transplantation, were included in this single center retrospective cohort study. The height for age Z score (HAZ) and length for age Z score (WAZ) at birth, at the time of transplantation and one year after transplantation were calculated respectively by collecting demographic characteristics, clinical manifestations, echocardiography, lipid-lowering treatment, blood lipid level data and donor characteristics data of liver transplantation. The serum cholesterol level and growing development changes before and after liver transplantation were evaluated. Results: A total of five patients with HoFH or cHeFH, including two females, were included in this study. The median age was 10 years (6-22 years). The median follow up duration was 28 months (24-33 months). All HoFH or cHeFH patients in this study received the maximum daily dosage of the lipid-lowering drug combined with low salt and low-fat diet control treatment for at least 3 months before orthotopic liver transplantation. The average level of total cholesterol (TC) decreased by 27% compared with that before treatment, the level of low-density lipoprotein cholesterol (LDL-C) decreased by 21% after 3 months treatment. There was no intervention of lipid-lowering therapy after operation. One month after liver transplantation, the average levels of TC and LDL-C further decreased rapidly by 68% and 76% respectively. One year after liver transplantation, the level of LDL-C decreased from (17.1±1.6)mmol/L without any intervention before transplantation to (3.0±0.7)mmol/L, and remained stable thereafter. In addition, compared with no intervention before liver transplantation, the serum triglyceride (TG) level decreased after the maximum daily dosage of the lipid-lowering drug and low salt and low-fat diet control for 3 months ((1.88±0.27) mmol/L vs. (1.12±0.55)mmol/L, P=0.031), and the HDL-C level also decreased significantly ((1.95±0.49)mmol/L vs. (0.95±0.30)mmol/L, P=0.006) at the same time period. TG and HDL-C remained stable after liver transplantation during the 24-month follow-up period (P>0.05). One and two years after liver transplantation, there was no significant difference in height and weight, malnutrition and growth retardation between the patients in this cohort and Chinese children of the same age. Conclusion: Early liver transplantation is a feasible and effective treatment option for HoFH or cHeFH patients with extremely high serum low-density lipoprotein cholesterol levels.
Child ; Infant, Newborn ; Female ; Humans ; Cholesterol, LDL/therapeutic use* ; Liver Transplantation ; Homozygous Familial Hypercholesterolemia ; Retrospective Studies ; Hyperlipoproteinemia Type II/surgery* ; Lipids ; Hypolipidemic Agents/therapeutic use*

Humans ; Female ; Coronary Artery Disease/complications* ; Hyperlipoproteinemia Type II/complications* ; Aortic Valve Stenosis/etiology* ; Treatment Outcome

Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease caused by abnormal lipoprotein metabolism. Patients with FH have a significantly increased risk of coronary artery disease (CAD) due to long-term exposure to high levels of low-density lipoprotein (LDL). The diagnosis of FH relies heavily on gene detection, and examination of LDL receptor (LDLR) function is of great significance in its treatment. This review summarizes the current advances in the screening, diagnosis, and treatment of FH and functional analysis of LDLR gene mutations.
Humans ; Hyperlipoproteinemia Type II/therapy* ; Coronary Artery Disease ; Lipoproteins, LDL ; Mutation

OBJECTIVE: To analyze variant of LDLR gene in a patient with familial hypercholesterolemia (FH) in order to provide a basis for the clinical diagnosis and genetic counseling. METHODS: A patient who had visited the Reproductive Medicine Center of the First Affiliated Hospital of Anhui Medical University in June 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was applied to the patient. Candidate variant was verified by Sanger sequencing. Conservation of the variant site was analyzed by searching the UCSC database. RESULTS: The total cholesterol level of the patient was increased, especially low density lipoprotein cholesterol. A heterozygous c.2344A>T (p.Lys782*) variant was detected in the LDLR gene. Sanger sequencing confirmed that the variant was inherited from the father. CONCLUSION The heterozygous c.2344A>T (p.Lys782*) variant of the LDLR gene probably underlay the FH in this patient. Above finding has provided a basis for genetic counseling and prenatal diagnosis for this family.
Humans ; Cholesterol, LDL/genetics* ; Heterozygote ; Hyperlipoproteinemia Type II/genetics* ; Mutation ; Pedigree ; Phenotype ; Receptors, LDL/genetics*

Objective: To identify and analyze 3D architecture of the mutational sites of susceptible genes in a pedigree with familial hypercholesterolemia-like phenotype (FHLP). Methods: This is a case series study. A pedigree with suspected familial hypercholesterolemia was surveyed. The proband admitted in Beijing Anzhen Hospital in April 2019. Whole-exome sequencing was performed to determine the mutational sites of susceptible genes in the proband. Polymerase chain reaction (PCR) sequencing was used to verify the pathogenic variant on proband's relatives. The structural and functional changes of the proteins were analyzed and predicted by Discovery Studio 4.0 and PyMol 2.0. Results: The patients in the pedigree showed abnormal lipid profiles, especially elevated levels of total cholesterol(TC). The genetic screening detected the c.1330C>T SNP in the exon 8 of lipase C (LIPC) gene, this mutation leads to an amino acid substitution from arginine to cysteine at position 444 (Arg444Cys), in the proband and proband's father and brother. In this family, members with this mutation exhibited elevated TC, whereas lipid profile was normal from the proband's mother without this mutation. This finding indicated that LIPC: c.1330C>T mutation might be the mutational sites of susceptible genes. The analysis showed that Arg444Cys predominantly affected the ligand-binding property of the protein, but had a limited impact on catalytic function. Conclusion: LIPC: c.1330C>T is a new mutational site of susceptible genes in this FHLP pedigree.
Humans ; Male ; Hyperlipoproteinemia Type II/genetics* ; Lipase/genetics* ; Lipids ; Mutation ; Pedigree ; Phenotype ; Proteins

Genetic Testing ; Humans ; Hyperlipoproteinemia Type II/genetics* ; Pedigree ; Receptors, LDL/genetics*

Antiviral Agents ; Cholesterol, LDL ; Humans ; Hyperlipoproteinemia Type II ; Proprotein Convertase 9/genetics*

OBJECTIVE: To explore the correlation between clinical phenotypes and pathogenic variants in two patients with familial hypercholesterolemia. METHODS: Both patients were subjected to whole exome sequencing (WES) with a focus on the analysis of genes associated with dyslipidemia. Candidate variants were verified by Sanger sequencing of the patients and their family members. RESULTS: WES revealed that the proband 1 has harbored two heterozygous variants of the LDLR gene, namely c.1360G>A (p.D454N) and c.292G>A (p.G98S), whilst proband 2 has harbored a heterozygous c.321T>G (p.C107W) variant of the LDLR gene. Based on the guidelines from the American College of Medical Genetic and Genomics (ACMG), the above variants were respectively predicted to be likely pathogenic (PM1+PM2+PP2+PP3+PP4+PP5), variant of unknown significance (PM1+PP2+PP3), and likely pathogenic (PM1+PM2+PP2+PP4+PP5). Treatment with PCSK9 inhibitor has attained a significant effect in proband 1 but no apparent effect in proband 2. CONCLUSION Variants of the LDLR gene probably underlay the familial hypercholesterolemia in the two pedigrees. The difference in the severity of the clinical phenotypes and response to PCSK9 inhibitor treatment between the two probands may be attributed to the different genotypes of the LDLR gene. Genetic testing not only can provide a basis for clinical diagnosis, but also facilitate the choice of lipid-lowering drugs.
Humans ; China ; Hyperlipoproteinemia Type II/genetics* ; Phenotype ; Receptors, LDL/genetics*

Objective: To investigate the clinical characteristics of hereditary hypercholesterolemia in childhood. Methods: The clinical data including general conditions, clinical manifestations, laboratory tests, and genetic testing results of 4 children with hereditary hypercholesterolemia who admitted to Henan Children's Hospital from January 2020 to December 2020 were retrospectively analyzed. Results: There were 4 female children aged 5.5,1.5,6.3,3.1 years, all presented with skin xanthoxoma as the chief complaint. Plasma total cholesterol (range 11.8 to 20.9 mmol/L) and low density lipoprotein-cholesterol (range 8.2 to 13.7 mmol/L) were significantly elevated. The serum β-glutamate levels in case 1 (241.2 μmol/L) and case 2 (164.2 μmol/L) increased significantly. Genetic analysis revealed compound heterozygous variants of ABCG8 gene in case 1 and ABCG5 gene in case 2 who were diagnosed with sitosterolemia. Case 3 and 4 who all had family history of hypercholesterolemia and compound heterozygous variants of LDLR gene were diagnosed with familial hypercholesterolemia. After diet treatment, the blood lipids returned normal and the skin xanoma subsided in case 1 and 2. In case 3 and 4, the blood lipids gradually decreased after diet and rosuvastatin treatment. Conclusions: Xanthomatosis is the common clinical manifestation of sitosterolemia and familial hypercholesterolemia. Family history, blood plant sterol profile, genetic variation, and changes in blood lipids after early dietary treatment are helpful for disease identification.
Child ; Humans ; Hypercholesterolemia/genetics* ; Retrospective Studies ; Hyperlipoproteinemia Type II/genetics* ; Cholesterol, LDL