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1.P.279 Effect of XbaI polymorphism of apolipoprotein B gene on response to lipid lowering therapy in type II hypercholesterolemic patients
Monday 6 October 1997: Posters Genetic epidemiology observed in liver chromatin of mice expressing a human ape(a) transgene. Neither enhancer exhibits tissue specificity. HSIII activity was mapped to a 600 bp fragment which stimulates luciferase expression from the ape(a) promoter 20 fold in HepG2 cells. The ubiquitous transcription factor Spl plays a major role in the function of this enhancer. HSIII comprises part of the regulatory region of a non-functional LINE-l retrotransposon, raising the possibility that retrotransposon insertion can influence the regulation of adjacent genes. HSII enhancer activity (6 fold) was localised to a 180 bp fragment. Mutations within an Spl site or an imperfect repeat of the nuclear hormone receptor half-site TGACCT in this sequence abolished enhancer function. Polymorphisms which may affect enhancer function are currently being sought.
1 1 .P.277 ( Mutations of the anti-oncogene ~53 and relations with the formation of tbe atherosclerosis of the atherosclerosis in Chinese adults Yu Wang, Tiande Li, Jianwei Liu, Zhiyuan Gu, Xiaoming Zhang, Xinzin Deng, Tingoku Yang, Guoshu Liu. Department of Cardiology; Chinese PLA General Hostpial, Faxing Street 2&f; Beijing, 100853, China
PR
For further understanding the pathogenesis of the human atherosclerosis (AS) lesions and the relations with the p52 anti-oncogene, which suppressing abnormal cellular proliferations and uncontrolled cellular devisions, the multi-hotspots mutations of p53 gene in human AS plaques and the relations with AS damage were studied detailedly, and some new viewpoints about the formations of AS were suggested. Controlling by Chinese healthy adults’ normal artery cells and healthy adults’ normal blood lymphocytes (DNA), the mutations of p53 gene in totally 89 cases of Chinese adults’ AS plaques were studied detailedly and systematically; including medium calibre muscular-elastic arteries and large calibre elastic arteries. The pathologic studies and biochemical studies were also made at the same time. It is found in our researches that: there were definite multi-hotspots mutations of p53 gene in Chinese human atherosclerotic plaques in 9 cases (ratio of mutations was 9/89) be detected by a a-32 p-dCTP radiative labelled polymerase chain reaction-single strand conformation polymorphism analysis (PCR-SSCP), and especially there were more frequent mutations in the exone, exont of p53 gene, and the mutations had been verified by dideaxy chain termination sequencing. By immuno-histochemical methods (~53 DO-l monoclonal antibody, Santa Cruz Biotech,) and special staining method of vascular elastic membrance (Victoria blue/Nuclear fast red elastic stain), the pathologic studies results showed: the case which had p53 DNA mutations verified by PCR-SSCP (electropharesis shifts positive change) also had the positive p53 DO-l stain. Compared with the non-mutative group, the vascular remnant section area ratio (ratio.1) and the vascular plaque thickness ratio (ratio.2) had more remarkable differences in mutations group (ratio.1: 0.6487 vs. 0.7371, P < 0.025; ratio.2 0.4618 vs. 0.4161, P 4 0.05). The biochemical analyses results of lipids in AS plaques and in serum showed: the TC, TG and CE contents in AS vascular walls in mutation group were more than that in negative group (ANOV: F = 4.56-9.97, p < 0.05-0.01); no differences in PL contents; me serum levels of LDL,-C, HDL-C, Lp(a), apoB2m between two groups have statistically difference:, but there were no statistic differences in serum levels of TC, TG, CE and apoAI between two groups (P > 0.05-0.25). In conclusion, it was definite that there were certain ratio mutations of anti-oncogene ~58 in some Chinese adults’ AS plaque cells, the narrowing extension of artery lumina in mutation group was more remarkable and the levels of some lipids content in AS plaques of mutation group were much higher. So, it was suggested strongly that, in the course of the formings and developings of human AS diseases, in addition to the abnormal high levels of serum lipoprotein and/or apolipoprotein should be considered as one of a major mechanisms, the mutations of anti-oncogene p53 which suppressing the abnormal cellular proliferations and uncontrolled cell divisions should also be thought over as another more important mechanism in the etiology of AS disease as well, while the levels of serum lipoproteins were in normal ranges. 1 P 278 ELI
Genetic variation in the apolipoprotein CIII gene and effects on plasma triglyceride levels in a large prospective study
Dawn M. Waterworth’, Philippa Talmud’, George Miller?, Steve Humphries’ ‘Dept Medicine, University College London; Wolfson Institute of Preventive Medicine, London, UK The SstI polymorphic
site, present
in the 3’ UTR
*MKC
of the (apo) CIII
11th International
gene, has
Symposium
15
been consistently associated with raised triglyceride (Tg) levels and CAD. The promoter region of this gene also contains a number of sequence changes, one of which ablates an insulin responsive element (IRE); these variants are in strong allelic iassociation with the SstI polymorphic site. We have investigated the association of SstI alleles with plasma Tg and cholesterol levels in the Northwick Park Heart Study (NPHSII) in a large prospective series of healthy men (n = 2416). SstI genotype was strongly associated with both baseline Tg (ANOVA, p = 0.0001) and the weighted average over 5 years (ANOVA, p = 0.0801). Sl/Sl (n = 2070) subjects had the lowest average weighted Tg (1.81 mmol/l), with Sl/S2 individuals (n = 358) having intermediate Tg values (2.05 rnmol/l); S2&2 individuals (n = 18) had the highest triglycerides (2.18 mmoVI). There was no significant interaction between SstI genotype and BMI with respect to triglyceride levels. No relationship was observed between the SstI genotype and cholesterol levels. The IRE has been investigated in a subset of NPHSII (n = 341) and shows borderline significance for genotype and Tg in a pairwise test of Sl/Sl and Sl/S2 (p = 0.04). By comparison the SstI genotype in the same group had a highly statistically significant effect on plasma Tg (ANOVA, p = 0.006). We are currently extending this analysis to include the whole study group, in order to clarify whether variation in the IRE can explain the effect of the SstI site on Tg levels or whether, as the pilot data suggests, variation at the SstI site is acting as a marker for genetic changes elsewhere in the apoAI-CIII-AIV gene cluster or possibly is itself functional.
1 1 .P.279
)
Etffect of XbaI polymorphism of apolipoprotein response to lipid lowering therapy in type II hypercholesterolemic patients
P., YZ. Shang, S.W. Wang, X.Y. Liu. Division of Geriatric Chinese PLA General Hospital, Beijing 100853, PR China
B gene on
Cardiology,
A wide inter-individual variation in response to lipid lowering therapy has been observed, although a good efficacy of such therapy has been documented. The aim of the present study was to investigate the possible role of apolipoprotem B (apo B) XbaI genotype on this variation. The apo B XbaI genotype was determined in 89 patients with non-familial type II hypercholesterolemia. Simvastatin (5 mg/day) was administered to 62 patients and theofibrate (500 mg/day) to 27 patients among the total. Only two genotypes were detected (X+Xand X-X-) with a relative frequency of X+ allele of 0.101 in this studied population. The baseline mean levels of lipid and apolipoprotein were not significantly different among the XbaI genotypes. Although the average decrease in total and LDL-cholesterol was somewhat greater in patients with X-Xgenotype compared with those with X+Xgenotype (-33% vs. -28%, -26% vs. -17% respectively) after 12 weeks of treatment, the differences were not statisticahy significant. Besides, there were no significant difference in changes of other measured lipid and apolipoprotein parameters between the two genotypes. Therefore, it is suggested that the inter-individual variation in response to lipid lowering therapy in non-familial hypercholesterolemic patients is the result of other factors beyond the apoB XbaI genotype.
GENETIC EPIDEMIOLOGY I1
P.280
A common substitution Ue4O!Wal in the choiesteryl eater transfer protein (CETP) is associated with increased HDL cholesterol and apolipoprotein Al. Studies in a general population sample of 8,989 women and men
Birait Agerholm-Larsen, Berge G. Nordestgaard, Germ Jensen, Anne Tybjerg-Hansen. Department of Clinical Biochemistry, Herlev Hospital and the Copenhagen City Heart Study, University of Copenhagen, Denmark
Background: CETP facilitates
exchange of cholesterol from and triglycerides to HDL particles. Mutations in the CETP gene may therefore affect HDL cholesterol levels and possibly risk of ischaemic heart disease. We tested the hypothesis that the lle405Val substitution in CETP might have such an effect. Methods: We genotyped 4,983 women and 4,006 men from a general population sample (the Copenhagen City Heart Study) using conventionel PCR and restriction enzyme digestion. Results: The relative frequencies of the lleille, lle/Val, and Val/Val phenotypes were 0.46,0.43, and 0. I I for both women and men. Women with lle/lle, lle/Val, and VaWal had mean (95% confidence interval) HDL cholesterol levels (mmol/L) of 1.68 (l&-1.70), 1.75 (1.73-1.78), and 1.81 (1.77-1.86), respectively (ANOVA: p -z 0.001). The equivalent apolipoprotein Al levels
on Atherosclerosis,
Paris,
October
1997
1 1 .P.277 ( Mutations of the anti-oncogene ~53 and relations with the formation of tbe atherosclerosis of the atherosclerosis in Chinese adults Yu Wang, Tiande Li, Jianwei Liu, Zhiyuan Gu, Xiaoming Zhang, Xinzin Deng, Tingoku Yang, Guoshu Liu. Department of Cardiology; Chinese PLA General Hostpial, Faxing Street 2&f; Beijing, 100853, China
PR
For further understanding the pathogenesis of the human atherosclerosis (AS) lesions and the relations with the p52 anti-oncogene, which suppressing abnormal cellular proliferations and uncontrolled cellular devisions, the multi-hotspots mutations of p53 gene in human AS plaques and the relations with AS damage were studied detailedly, and some new viewpoints about the formations of AS were suggested. Controlling by Chinese healthy adults’ normal artery cells and healthy adults’ normal blood lymphocytes (DNA), the mutations of p53 gene in totally 89 cases of Chinese adults’ AS plaques were studied detailedly and systematically; including medium calibre muscular-elastic arteries and large calibre elastic arteries. The pathologic studies and biochemical studies were also made at the same time. It is found in our researches that: there were definite multi-hotspots mutations of p53 gene in Chinese human atherosclerotic plaques in 9 cases (ratio of mutations was 9/89) be detected by a a-32 p-dCTP radiative labelled polymerase chain reaction-single strand conformation polymorphism analysis (PCR-SSCP), and especially there were more frequent mutations in the exone, exont of p53 gene, and the mutations had been verified by dideaxy chain termination sequencing. By immuno-histochemical methods (~53 DO-l monoclonal antibody, Santa Cruz Biotech,) and special staining method of vascular elastic membrance (Victoria blue/Nuclear fast red elastic stain), the pathologic studies results showed: the case which had p53 DNA mutations verified by PCR-SSCP (electropharesis shifts positive change) also had the positive p53 DO-l stain. Compared with the non-mutative group, the vascular remnant section area ratio (ratio.1) and the vascular plaque thickness ratio (ratio.2) had more remarkable differences in mutations group (ratio.1: 0.6487 vs. 0.7371, P < 0.025; ratio.2 0.4618 vs. 0.4161, P 4 0.05). The biochemical analyses results of lipids in AS plaques and in serum showed: the TC, TG and CE contents in AS vascular walls in mutation group were more than that in negative group (ANOV: F = 4.56-9.97, p < 0.05-0.01); no differences in PL contents; me serum levels of LDL,-C, HDL-C, Lp(a), apoB2m between two groups have statistically difference:, but there were no statistic differences in serum levels of TC, TG, CE and apoAI between two groups (P > 0.05-0.25). In conclusion, it was definite that there were certain ratio mutations of anti-oncogene ~58 in some Chinese adults’ AS plaque cells, the narrowing extension of artery lumina in mutation group was more remarkable and the levels of some lipids content in AS plaques of mutation group were much higher. So, it was suggested strongly that, in the course of the formings and developings of human AS diseases, in addition to the abnormal high levels of serum lipoprotein and/or apolipoprotein should be considered as one of a major mechanisms, the mutations of anti-oncogene p53 which suppressing the abnormal cellular proliferations and uncontrolled cell divisions should also be thought over as another more important mechanism in the etiology of AS disease as well, while the levels of serum lipoproteins were in normal ranges. 1 P 278 ELI
Genetic variation in the apolipoprotein CIII gene and effects on plasma triglyceride levels in a large prospective study
Dawn M. Waterworth’, Philippa Talmud’, George Miller?, Steve Humphries’ ‘Dept Medicine, University College London; Wolfson Institute of Preventive Medicine, London, UK The SstI polymorphic
site, present
in the 3’ UTR
*MKC
of the (apo) CIII
11th International
gene, has
Symposium
15
been consistently associated with raised triglyceride (Tg) levels and CAD. The promoter region of this gene also contains a number of sequence changes, one of which ablates an insulin responsive element (IRE); these variants are in strong allelic iassociation with the SstI polymorphic site. We have investigated the association of SstI alleles with plasma Tg and cholesterol levels in the Northwick Park Heart Study (NPHSII) in a large prospective series of healthy men (n = 2416). SstI genotype was strongly associated with both baseline Tg (ANOVA, p = 0.0001) and the weighted average over 5 years (ANOVA, p = 0.0801). Sl/Sl (n = 2070) subjects had the lowest average weighted Tg (1.81 mmol/l), with Sl/S2 individuals (n = 358) having intermediate Tg values (2.05 rnmol/l); S2&2 individuals (n = 18) had the highest triglycerides (2.18 mmoVI). There was no significant interaction between SstI genotype and BMI with respect to triglyceride levels. No relationship was observed between the SstI genotype and cholesterol levels. The IRE has been investigated in a subset of NPHSII (n = 341) and shows borderline significance for genotype and Tg in a pairwise test of Sl/Sl and Sl/S2 (p = 0.04). By comparison the SstI genotype in the same group had a highly statistically significant effect on plasma Tg (ANOVA, p = 0.006). We are currently extending this analysis to include the whole study group, in order to clarify whether variation in the IRE can explain the effect of the SstI site on Tg levels or whether, as the pilot data suggests, variation at the SstI site is acting as a marker for genetic changes elsewhere in the apoAI-CIII-AIV gene cluster or possibly is itself functional.
1 1 .P.279
)
Etffect of XbaI polymorphism of apolipoprotein response to lipid lowering therapy in type II hypercholesterolemic patients
P., YZ. Shang, S.W. Wang, X.Y. Liu. Division of Geriatric Chinese PLA General Hospital, Beijing 100853, PR China
B gene on
Cardiology,
A wide inter-individual variation in response to lipid lowering therapy has been observed, although a good efficacy of such therapy has been documented. The aim of the present study was to investigate the possible role of apolipoprotem B (apo B) XbaI genotype on this variation. The apo B XbaI genotype was determined in 89 patients with non-familial type II hypercholesterolemia. Simvastatin (5 mg/day) was administered to 62 patients and theofibrate (500 mg/day) to 27 patients among the total. Only two genotypes were detected (X+Xand X-X-) with a relative frequency of X+ allele of 0.101 in this studied population. The baseline mean levels of lipid and apolipoprotein were not significantly different among the XbaI genotypes. Although the average decrease in total and LDL-cholesterol was somewhat greater in patients with X-Xgenotype compared with those with X+Xgenotype (-33% vs. -28%, -26% vs. -17% respectively) after 12 weeks of treatment, the differences were not statisticahy significant. Besides, there were no significant difference in changes of other measured lipid and apolipoprotein parameters between the two genotypes. Therefore, it is suggested that the inter-individual variation in response to lipid lowering therapy in non-familial hypercholesterolemic patients is the result of other factors beyond the apoB XbaI genotype.
GENETIC EPIDEMIOLOGY I1
P.280
A common substitution Ue4O!Wal in the choiesteryl eater transfer protein (CETP) is associated with increased HDL cholesterol and apolipoprotein Al. Studies in a general population sample of 8,989 women and men
Birait Agerholm-Larsen, Berge G. Nordestgaard, Germ Jensen, Anne Tybjerg-Hansen. Department of Clinical Biochemistry, Herlev Hospital and the Copenhagen City Heart Study, University of Copenhagen, Denmark
Background: CETP facilitates
exchange of cholesterol from and triglycerides to HDL particles. Mutations in the CETP gene may therefore affect HDL cholesterol levels and possibly risk of ischaemic heart disease. We tested the hypothesis that the lle405Val substitution in CETP might have such an effect. Methods: We genotyped 4,983 women and 4,006 men from a general population sample (the Copenhagen City Heart Study) using conventionel PCR and restriction enzyme digestion. Results: The relative frequencies of the lleille, lle/Val, and Val/Val phenotypes were 0.46,0.43, and 0. I I for both women and men. Women with lle/lle, lle/Val, and VaWal had mean (95% confidence interval) HDL cholesterol levels (mmol/L) of 1.68 (l&-1.70), 1.75 (1.73-1.78), and 1.81 (1.77-1.86), respectively (ANOVA: p -z 0.001). The equivalent apolipoprotein Al levels
on Atherosclerosis,
Paris,
October
1997