Association between -14 bp and ZNF polymorphisms of ABCA1 gene promoter and high density lipoprotein cholesterol level and cardiovascular disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association between polymorphisms at -14 bp and zinc finger protein(ZNF) sites of ATP-binding cassette transporter A1 (ABCA1) gene promotor and high density lipoprotein-cholesterol (HDL-C) level and coronary heart disease (CHD).</p><p><b>METHODS</b>Polymorphisms of Bme13901 restriction site at -14 bp and an insertion/deletion site of ACCCC in variable number of tandem repeats-zinc finger protein(VNTR-ZNF) of ABCA1 gene were detected using PCR in 260 CHD patients and 220 healthy subjects from a Chinese population in Tianjin.</p><p><b>RESULTS</b>CT genotype was most common in both groups with no differences found in between (P> 0.05). No differences were found in the frequencies of the rare T allele for -14 bp (P> 0.05). For the -14 bp site, subjects with CT/TT genotype had a lower serum mean concentration of HDL-C compared with those with the CC genotype (P< 0.05). Genotypic frequencies of VNTR-ZNF were 6.2% for the inserted form, 43.8% for the deleted form and 50.0% for the inserted/deleted form. No significant difference was found in the distribution of allele and genotype, or in the levels of HDL-C between the two groups (P> 0.05).</p><p><b>CONCLUSION</b>The genotypes at -14 bp of ABCA1 gene are associated with the plasma level of HDL-C. HDL-C levels in T allele carriers were significantly lower (P< 0.05). No association was found between variations in ABCA1 VNTR-ZNF and plasma levels of HDL-C, or between the ABCA1 -14 bp and VNTR-ZNF polymorphisms and susceptibility for CHD.</p>

The effect of gene polymorphism in promoter and intron 1 on human ApoA I expression / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To construct pGL2-ApoA I luciferase reporter vector containing ApoA I gene regulation area, and to investigate the effect of G --> A and C --> T substitution in ApoA I promoter -75 bp and intron 1 +83 bp region respectively on ApoA I gene expression.</p><p><b>METHODS</b>Human chromosome DNA fragments containing ApoA I gene were amplified by PCR, and the DNA fragments consisting of ApoA I AA/CC, GG/TT and GG/CC genetypes were selected separately, then pUC vector including above three different DNA fragments was constructed. After digesting pUC vector with Sac I and Bgl II, ligate the different DNA fragments to basic pGL2 vector that containing luciferase reporter gene. Recombinant and PRL-null vector were cotransfected into HepG2 cells by using cationic liposome method. Cells were cultured for 48 h, activity of firefly and renills luciferase was measured.</p><p><b>RESULTS</b>Three vectors with pGL2-ApoA I-L(-2500 to +289 bp) long fragment vectors and 3 with pGL2-ApoA I-S(-145 to +289 bp) short fragment vectors were combinated successfully. Relative activity of luciferase for ApoA I AA/CC or GG/TT was lower than that for GG/CC significantly.</p><p><b>CONCLUSION</b>-75 bp G --> A and +83 bp C --> T substitution in ApoA I gene may inhibit ApoA I gene transcription and expression. It may be the reason why subjects containing -75 bp A and +83 bp T have lower high density lipoprotein cholesterol (HDL-C) concentration.</p>