Identification and haplotype analysis of apolipoprotein B-100 Arg3500→Trp mutation in hyperlipidemic Chinese

Abstract

DNA screening for apolipoprotein (apo) B-100 mutations was performed in hyperlipidemic Chinese. The apo B-100 gene segment surrounding previously identified familial defective apo B-100 (FDB) mutations was amplified by PCR and subjected to single-strand conformation polymorphism (SSCP) analysis. One subject’s aberrant SSCP band was cloned and sequenced to study the molecular lesions. A recurrent ArgCGG-to-TrpTGG mutation (R3500W) in the codon 3500 of the apo B-100 gene was identified. The C-to-T transition creates a NlaIII site and permits rapid restriction analysis of the mutation. A total of 373 hyperlipidemic patients and 309 controls were screened for R3500W. Nine unrelated subjects were shown to be heterozygous for the mutation, and no R3500W carriers were found in the control group (P = 0.004). Six polymorphic markers, including five restriction fragment length polymorphisms and one hypervariable repeat region, were used for haplotype analysis on the mutant allele. In two families, the R3500W mutation could be unambiguously assigned to a unique haplotype XbaI−/MaeI+/MspI+/EcoRI+/Eco57I+/34 3′HVR repeats; in the other seven unrelated heterozygotes, this finding was consistent when an unequivocal haplotype was deduced. The results suggest that all R3500W alleles are identical by descent in our population. The fact that the same mutant allele was identified in other Asians with FDB indicates a common Asian origin for the R3500W mutations.

Mucopolysaccharidosis type I: Characterization of novel mutations affecting α‐ l‐iduronidase activity

“…The specific PCR conditions are listed in Table 1. Nonisotopic SSCP analysis and DNA sequencing were carried out as described [13] except that two conditions (8 and 15°C) were used for the nondenaturing gel electrophoresis. Four to six independent clones containing aberrant exon 14 were sequenced.…”

Familial Hypercholesterolemia: The Lipids or the Genes?

“…It is common in Europe accounting to 2-5% of the FH phenotype [ 24 ]. Another variant at the same position (Arg3500Trp) is common in the Chinese population [ 25 ]. As a cause of ADH, ApoB-100 is relatively uncommon compared to LDLR mutations.…”

The Roles of Genetic Polymorphisms and Human Immunodeficiency Virus Infection in Lipid Metabolism

“…The apo B gene is located on chromosome 2p23-p24, and several mutations and SNPs are associated with either variations in plasma lipid concentrations [ 79 ] or with CAD and myocardial infarction [ 99 – 101 ]. The SNPs in apo B include the Xba I at exon 26 (C7673T, rs693), Eco RI at exon 29 (G12669A, rs1042031), Msp I at exon 26 (rs676210), an indel at exon 1 within the signal peptide (rs17240441), and a hypervariable region at the 3′ end (3′HVR) [ 102 , 103 ].…”