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Genetic Epidemiology of Lipoprotein-Lipid Levels

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00005335
First Posted: May 26, 2000
Last Update Posted: May 13, 2016
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
  Purpose
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.

Condition
Cardiovascular Diseases Heart Diseases Atherosclerosis

Study Type: Observational

Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: May 1991
Study Completion Date: March 2002
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.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

  Eligibility

Information from the National Library of Medicine

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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria
No eligibility criteria
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00005335


Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Investigators
OverallOfficial: Mohammad Kamboh University of Pittsburgh
  More Information

Publications:

ClinicalTrials.gov Identifier: NCT00005335     History of Changes
Other Study ID Numbers: 4192
R01HL044672 ( U.S. NIH Grant/Contract )
First Submitted: May 25, 2000
First Posted: May 26, 2000
Last Update Posted: May 13, 2016
Last Verified: July 2004

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases
Atherosclerosis
Arteriosclerosis
Arterial Occlusive Diseases
Vascular Diseases