低密度脂蛋白受体基因突变及功能检测和临床应用进展

doi:10.3969/j.issn.1673-8640.2021.12.019

摘要/Abstract

摘要：

低密度脂蛋白受体（LDLR）是一种细胞表面糖蛋白,在维持体内胆固醇代谢平衡方面具有重要作用。LDLR基因突变会引起细胞表面LDLR减少或缺如,导致胆固醇代谢能力降低,血浆低密度脂蛋白胆固醇（LDL-C）水平升高并沉积在不同的组织和器官,引起多种脂代谢紊乱性疾病。准确、快速地检测LDLR基因突变,分析LDLR功能改变,对家族性高胆固醇血症（FH）患者的诊断及鉴别诊断至关重要。文章就LDLR基因突变及功能检测的方法学与临床应用新进展加以综述,以提高临床对LDLR在FH患者早期诊治与干预的认识。

关键词: 低密度脂蛋白受体, 低密度脂蛋白胆固醇, 脂质代谢, 基因突变

Abstract:

Low-density lipoprotein receptor（LDLR） is one type of cell surface glycoprotein,which plays a role in maintaining cholesterol metabolism balance in vivo. LDLR gene mutation can cause the decreasing,even the absence of LDLR on the cell surface,reduce the body's ability to metabolize cholesterol,lead to elevated plasma low-density lipoprotein cholesterol（LDL-C） level and deposition in different tissues and organs,and cause a variety of lipid metabolism disorders. Accurate and rapid determination of LDLR gene mutations and analysis of changes in LDLR function are essential for the diagnosis and differential diagnosis of familial hypercholesterolemia（FH）. This review focuses on the progress in the methodology and clinical application of LDLR gene mutation and function determination,in order to raise awareness and concern of its importance in early diagnosis and intervention of FH patients.

Key words: Low-density lipoprotein receptor, Low-density lipoprotein cholesterol, Lipid metabolism, Gene mutation

中图分类号:

R446.1

朱勇琳, 王绿娅, 鄢盛恺. 低密度脂蛋白受体基因突变及功能检测和临床应用进展[J]. 检验医学, 2021, 36(12): 1287-1291.

ZHU Yonglin, WANG Lüya, YAN Shengkai. Research progress in the methodology and clinical application of low-density lipoprotein receptor gene mutation and function determination[J]. Laboratory Medicine, 2021, 36(12): 1287-1291.

图/表 3

参考文献 30

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检测方法	原理	优点	缺点	应用示例
Sanger测序	利用双脱氧核苷酸可终止聚合酶联反应的原理	可检测长序列和5%的小等位基因片段;基因测序金标准;样本少时效益高	样本多时效益低;成本高;速度慢	225例受试者中发现了LDLR基因的7个致病突变和5个良性突变^[10]。
NGS	通过捕捉新添加碱基携带的特殊标记来确定DNA序列	高通量;可同时测序多个基因;可发现新变异;测序深度、灵敏度高	样本少时效益低;需进行生物信息学分析	148例阳性突变患者中发现了77例LDLR基因杂合型突变和5例LDLR基因纯合型突变^[12]。
MLPA	在靶序列变异位点两侧设计1对探针,经杂交、连接、聚合酶联反应扩增、产物分离及数据分析后得出结果	CNV的金标准;简单、成本低;突变检测阴性后使用	仅针对LDLR基因;不能检测单细胞和未知位点;对探针附近新的良性多态性敏感	在新加坡人群中检出4例大的LDLR基因新重排突变^[13]。

检测方法	原理	优点	缺点	应用示例
Sanger测序	利用双脱氧核苷酸可终止聚合酶联反应的原理	可检测长序列和5%的小等位基因片段;基因测序金标准;样本少时效益高	样本多时效益低;成本高;速度慢	225例受试者中发现了LDLR基因的7个致病突变和5个良性突变^[10]。
NGS	通过捕捉新添加碱基携带的特殊标记来确定DNA序列	高通量;可同时测序多个基因;可发现新变异;测序深度、灵敏度高	样本少时效益低;需进行生物信息学分析	148例阳性突变患者中发现了77例LDLR基因杂合型突变和5例LDLR基因纯合型突变^[12]。
MLPA	在靶序列变异位点两侧设计1对探针,经杂交、连接、聚合酶联反应扩增、产物分离及数据分析后得出结果	CNV的金标准;简单、成本低;突变检测阴性后使用	仅针对LDLR基因;不能检测单细胞和未知位点;对探针附近新的良性多态性敏感	在新加坡人群中检出4例大的LDLR基因新重排突变^[13]。

类别	检测目的	检测方法	检测原理	应用情况
荧光分析法	LDLR的表达	抗体标记法	FACS检测LDLR抗体的荧光强度	常用
		间接免疫荧光法	FACS检测荧光二抗的荧光强度	常用
		免疫印迹法	凝胶图像处理系统分析条带强度	常用
	LDLR结合LDL的能力	FACS检测法	FACS定量检测LDLR结合LDL的量	常用
		CLSM检测法	CLSM可视化观察LDLR结合LDL	常用
放射性分析法	LDLR的表达	放射性物质标记法	化学发光法检测细胞内¹²⁵I-IgG-C7的放射性	常用（但正在被荧光分析法取代）
放射性分析法	LDLR结合LDL的能力	放射性物质标记法	化学发光法检测肝素的放射性	常用（但正在被荧光分析法取代）

类别	检测目的	检测方法	检测原理	应用情况
荧光分析法	LDLR的表达	抗体标记法	FACS检测LDLR抗体的荧光强度	常用
		间接免疫荧光法	FACS检测荧光二抗的荧光强度	常用
		免疫印迹法	凝胶图像处理系统分析条带强度	常用
	LDLR结合LDL的能力	FACS检测法	FACS定量检测LDLR结合LDL的量	常用
		CLSM检测法	CLSM可视化观察LDLR结合LDL	常用
放射性分析法	LDLR的表达	放射性物质标记法	化学发光法检测细胞内¹²⁵I-IgG-C7的放射性	常用（但正在被荧光分析法取代）
放射性分析法	LDLR结合LDL的能力	放射性物质标记法	化学发光法检测肝素的放射性	常用（但正在被荧光分析法取代）