Clinical and molecular characteristics of a family with familial hypercholesterolemia with LDLRAP1 and ABCG8 gene abnormality
10.3760/cma.j.cn114452-20211026-00660
- VernacularTitle:同时伴有LDLRAP1及ABCG8基因异常的家族性高胆固醇血症一家系的临床及分子生物学特征
- Author:
Jiaming LI
1
;
Zhenping PENG
;
Qiulan DING
;
Xuefeng WANG
;
Peipei JIN
Author Information
1. 上海交通大学医学院附属瑞金医院输血科，上海 200025
- Keywords:
Familial hypercholesterolemia;
Sitosterolemia;
Anemia;
Gene mutation
- From:
Chinese Journal of Laboratory Medicine
2022;45(3):252-259
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the clinical and molecular characteristics of a family with familial hypercholesterolemia (FH) with LDLRAP1 and ABCG8 gene abnormality.Methods:In September 2020, one case of FH was included in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine; peripheral venous blood samples of members of the family were collected to detect serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) indicators; use high-performance liquid chromatography to detect serum stigmasterol and sitosterol content; perform second-generation gene sequencing to detect gene mutations in probands and family members; use Pymol software to detect gene mutations point for pathogenicity analysis, and use Uniprot Modelling software to perform protein structure modeling.Results:The patient presented with anemia, multiple xanthomas and early-onset acute coronary syndrome. The coronary angiography showed severe coronary artery lesions; abdominal ultrasound showed splenomegaly; blood smear showed shaped erythrocytes and large platelets. The level of serum TC, LDL-C, stigmasterol and sitosterol was 8.54 mmol/L (2.3-5.7 mmol/L), 4.84 mmol/L (range of normal value 1.3-4.3 mmol/L), 44 μmol/L (1.0-10 μmol/L), 28 μmol/L (1.0-15 μmol/L), respectively; LDLRAP1 gene mutation was found: exon4 c.415C>T:p.Q139X; the truncated protein formed by this homozygous mutation lost multiple stable protein structure regions, which can not have a normal function. At the same time, ABCG8 gene mutations were also found: exon13 c.1895T>C (p.V632A) and exon8 c.1199C>A:p.T400K . Two cases of family members had a mild increase in HDL-C (Ⅱ5: 2.33 mmol/L, Ⅱ6∶2.96 mmol/L), 3 cases carrying the ABCG8 gene mutations had a slight increase in stigmasterol (Ⅱ8: 23 μmol/L, Ⅱ7: 24 μmol/L, Ⅰ2: 18 μmol/L) and sitosterol (Ⅱ8: 41 μmol/L, Ⅱ7: 33 μmol/L, Ⅰ2: 45 μmol/L), suggesting that its association with the concentration of plant sterols. Conclusions:FH patients with LDLRAP1 and ABCG8 gene abnormalities may have abnormal plant sterol concentrations, and their clinical manifestations are more complicated. Therefore, family history, LDL-C, plant sterol levels, and genetic test results should be considered comprehensively.
