학술논문
Identification and characterization of novel loss of function mutations in ATP-binding cassette transporter A1 in patients with low plasma high-density lipoprotein cholesterol.
Document Type
Academic Journal
Author
Candini C; Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena, Italy.; Schimmel AW; Peter J; Bochem AE; Holleboom AG; Vergeer M; Dullaart RP; Dallinga-Thie GM; Hovingh GK; Khoo KL; Fasano T; Bocchi L; Calandra S; Kuivenhoven JA; Motazacker MM
Source
Publisher: Elsevier Country of Publication: Ireland NLM ID: 0242543 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1879-1484 (Electronic) Linking ISSN: 00219150 NLM ISO Abbreviation: Atherosclerosis Subsets: MEDLINE
Subject
Language
English
Abstract
Objectives: The current literature provides little information on the frequency of mutations in the ATP-binding cassette transporter A1 (ABCA1) in patients with low high-density lipoprotein cholesterol (HDL) levels that are referred to the clinic. In 78 patients with low plasma levels of HDL cholesterol that were referred to our clinic, we routinely screened for ABCA1 gene mutations and studied the functionality of newly identified ABCA1 missense mutations.
Methods: The coding regions and exon-intron boundaries of the ABCA1 gene were sequenced in 78 subjects with HDL cholesterol levels below the 10th percentile for age and gender. Novel mutations were studied by assessing cholesterol efflux capacity (using apolipoprotein A-I as acceptor) after transient expression of ABCA1 variants in BHK cells.
Results: Sixteen out of 78 patients (21%) were found to carry 19 different ABCA1 gene variants (1 frameshift, 2 splice-site, 4 nonsense and 12 missense variation) of which 14 variations were novel. Of three patients with homozygous mutations and three patients having compound heterozygous mutations only one patient presented with the clinical characteristics of Tangier Disease (TD) in the presence of nearly complete HDL deficiency. Seven out of eight newly identified ABCA1 missense mutations were found to exhibit a statistically significant loss of cholesterol efflux capacity.
Conclusion: This study shows that one out of five patients who are referred to our hospital because of low HDL cholesterol levels have a functional ABCA1 gene mutation. It is furthermore demonstrated that in vitro studies are needed to assess functionality of ABCA1 missense mutations.
(Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)
Methods: The coding regions and exon-intron boundaries of the ABCA1 gene were sequenced in 78 subjects with HDL cholesterol levels below the 10th percentile for age and gender. Novel mutations were studied by assessing cholesterol efflux capacity (using apolipoprotein A-I as acceptor) after transient expression of ABCA1 variants in BHK cells.
Results: Sixteen out of 78 patients (21%) were found to carry 19 different ABCA1 gene variants (1 frameshift, 2 splice-site, 4 nonsense and 12 missense variation) of which 14 variations were novel. Of three patients with homozygous mutations and three patients having compound heterozygous mutations only one patient presented with the clinical characteristics of Tangier Disease (TD) in the presence of nearly complete HDL deficiency. Seven out of eight newly identified ABCA1 missense mutations were found to exhibit a statistically significant loss of cholesterol efflux capacity.
Conclusion: This study shows that one out of five patients who are referred to our hospital because of low HDL cholesterol levels have a functional ABCA1 gene mutation. It is furthermore demonstrated that in vitro studies are needed to assess functionality of ABCA1 missense mutations.
(Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)