[Hypermethylation in promoter area of LDLR gene in atherosclerosis patients].

To investigate the methylation pattern of 12 CpG dinucleotide sites in promoter region of LDLR gene in atherosclerosis patients, peripheral blood DNA samples were prepared from 61 atherosclerosis patients and 28 healthy subjects. The methylation status of CpG islands in LDLR gene promoter region was measured by using a modified coordinative method with nested-PCR, Touchdown-PCR and methylation-sensitive-single-strand conformation analysis (MS-SSCA). Three types of methylation patterns were detected in promoter region of LDLR gene in peripheral blood genome of atherosclerosis patients: full-methylation, part-methylation and none-methylation. 2 cases were full-methylation and 13 cases were part-methylation, the methylation frequency was 24.59% in atherosclerosis patients. While in 28 healthy control, only 1 half-methylation sample was found, the methylation frequency was 3.57%, which is much lower than that in atherosclerosis patients (P < 0.05). A significantly higher methylation degree in promoter region of LDLR gene was found in peripheral blood genome of atherosclerosis patients compared with the controlled healthy subjects, which may suggest an involvement of aberrant methylation of LDLR gene in initiation and development of AS. The modified coordinative method with nested-PCR, Touchdown-PCR and MS-SSCA manifests merits of convenience, cheap and high efficiency, which lowers the requirement for the DNA template and increases the sensitivity and specificity.