Genetic Epidemiology of Lipoprotein-Lipid Levels
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| First Received Date ICMJE | May 25, 2000 | ||||
| Last Updated Date | June 23, 2005 | ||||
| Start Date ICMJE | May 1991 | ||||
| Primary Completion Date | Not Provided | ||||
| Current Primary Outcome Measures ICMJE | Not Provided | ||||
| Original Primary Outcome Measures ICMJE | Not Provided | ||||
| Change History | Complete list of historical versions of study NCT00005335 on ClinicalTrials.gov Archive Site | ||||
| Current Secondary Outcome Measures ICMJE | Not Provided | ||||
| Original Secondary Outcome Measures ICMJE | Not Provided | ||||
| Current Other Outcome Measures ICMJE | Not Provided | ||||
| Original Other Outcome Measures ICMJE | Not Provided | ||||
| Descriptive Information | |||||
| Brief Title ICMJE | Genetic Epidemiology of Lipoprotein-Lipid Levels | ||||
| Official Title ICMJE | Not Provided | ||||
| Brief Summary | To determine the contribution of polymorphic variation in candidate genes involved in lipid metabolism in determining quantitative lipoprotein-lipid levels and cardiovascular risk factors in Anglo and Hispanic populations of the San Luis Valley in southern Colorado. The candidate genes included those for A-IV, B, D, E, H, APO(a), LDL receptor, hepatic lipase, lipoprotein lipase, lethicin cholesterol acyletransferase (LCAT), and cholesteryl ester transfer protein. |
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| Detailed Description | DESIGN NARRATIVE: Beginning in 1991, genetic variations in the gene products of A-IV, E, H, and APO(a) were determined by isoelectric focusing and SDS/immunoblotting; gene variations at the APOB, D, LDL receptor, hepatic lipase, lipoprotein lipase, and cholesteryl ester transfer protein were assayed by polymerase chain reaction protocols and by using cloned cDNA probes for restriction fragment length polymorphism (RFLP) analyses. Direct haplotype analyses of individuals employed a strategy using RFLP analysis combined with the use of allele specific oligonucleotides. Quantitative levels of apolipoprotein B, E, H and APO (a) were determined by immunological techniques. These data and prior data on levels of triglycerides, total cholesterol, HDL-, LDL- and HDL subfraction cholesterol were used in the quantitative genetic analysis. Estimates of the effect of alleles at each of the genetic loci on the quantitative apolipoprotein and lipoprotein levels employed the measured genotype approach. The effects of multisite haplotypes for RFLPs at various loci were estimated using the same methods. For common alleles in each system, estimates were made of the interaction of alleles at independent genetic loci in determining quantitative variables. Dietary information from the San Luis Valley population was used to estimate cholesterol intake identified. Allelic effects were estimated in these groups to gain insight into the effect of dietary cholesterol intake of the estimated allelic effects. The study was renewed in fiscal year 1996 to determine the contribution of polymorphic variation in nine candidate genes involved in lipid metabolism [APO(a), APOD, hepatic lipase (HL), cholesteryl ester transfer protein (CETP), LDL receptor related protein (LRP), 3- hydroxy-3 methyl glutryl-coenzyme A (HMG COA), VLDL-receptor, Lecithin cholesterol acyletransferase (LCAT) and paraoxonase (PON)] in determining quantitative lipoprotein-lipid levels in Hispanics and non-Hispanic Whites of the San Luis Valley, Colorado. The study also determined the molecular basis of the functional mutation in the lipoprotein lipase (LPL) gene which is associated with plasma triglyceride and HDL cholesterol variations. The objectives were achieved by fulfilling the following specific aims: 1) by PCR, DNA sequencing and SSCP analyses, all coding exons and putative regulatory elements in the LPL gene of individuals who were homozygous for the HindIII restriction site to detect nucleotide changes in the coding region which affected directly triglycerides and HDL-cholesterol levels werescreened, in vitro mutagenesis and expression studies were conducted to confirm which of the putative functional mutations was the actual functional mutation; 2) genetic variations in genes coding for CETP, HL, LRP, APOD, HMG COA, VLDL-receptor, LCAT and PON were identified by PCR or standard Southern blotting techniques, and the impact of individual polymorphisms and the joint impact of polymorphisms at different loci (genotype-genotype interaction) in determining quantitative lipoprotein-lipid levels in Hispanics and non-Hispanic whites were estimated; and 3) the distribution of APO(a) kringle 4 and pentanucleotide polymorphisms were determined by SDS-agarose gel electrophoresis and PCR, respectively, and LP(a) levels were quantified by enzyme-linked immunosorbent assay, and the correlation between APO(a) polymorphisms and LP(a) levels were investigated. |
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| Study Type ICMJE | Observational | ||||
| Study Design ICMJE | Observational Model: Natural History | ||||
| Target Follow-Up Duration | Not Provided | ||||
| Biospecimen | Not Provided | ||||
| Sampling Method | Not Provided | ||||
| Study Population | Not Provided | ||||
| Condition ICMJE |
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| Intervention ICMJE | Not Provided | ||||
| Study Group/Cohort (s) | Not Provided | ||||
| Publications * |
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* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline. |
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| Recruitment Information | |||||
| Recruitment Status ICMJE | Completed | ||||
| Enrollment ICMJE | Not Provided | ||||
| Completion Date | March 2002 | ||||
| Primary Completion Date | Not Provided | ||||
| Eligibility Criteria ICMJE | No eligibility criteria |
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| Gender | Both | ||||
| Ages | Not Provided | ||||
| Accepts Healthy Volunteers | No | ||||
| Contacts ICMJE | Contact information is only displayed when the study is recruiting subjects | ||||
| Location Countries ICMJE | Not Provided | ||||
| Administrative Information | |||||
| NCT Number ICMJE | NCT00005335 | ||||
| Other Study ID Numbers ICMJE | 4192 | ||||
| Has Data Monitoring Committee | Not Provided | ||||
| Responsible Party | Not Provided | ||||
| Study Sponsor ICMJE | National Heart, Lung, and Blood Institute (NHLBI) | ||||
| Collaborators ICMJE | Not Provided | ||||
| Investigators ICMJE |
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| Information Provided By | National Heart, Lung, and Blood Institute (NHLBI) | ||||
| Verification Date | July 2004 | ||||
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ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP |
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