Related Experiment Videos
Interaction between variant apolipoproteins C-II and E that affects plasma lipoprotein concentrations
R A Hegele1, W C Breckenridge, D W Cox
1Department of Medicine, St. Michael's Hospital, Toronto, Canada.
Arteriosclerosis and Thrombosis : a Journal of Vascular Biology
|September 1, 1991
Summary
Apolipoprotein C-II (apo C-II) gene mutations can cause severe lipid disorders. Coinheriting apo C-II and apo E variants interact to influence cholesterol and triglyceride levels.
Area of Science:
- Genetics
- Molecular Biology
- Biochemistry
Background:
- Apolipoprotein C-II (apo C-II) is crucial for activating lipoprotein lipase.
- Apolipoprotein E (apo E) plays a role in lipoprotein clearance.
- These genes are located on chromosome 19q13.1.
Purpose of the Study:
- Investigate the impact of apo C-II mutations on lipoprotein lipase activity.
- Examine the lipid profiles of individuals with apo C-II mutations.
- Determine if apo E variants modify the lipid phenotype in apo C-II mutation carriers.
Main Methods:
- Studied a large Caribbean Caucasian family with apo C-II mutations.
- Assessed lipoprotein lipase activity in vitro.
- Analyzed serum lipid and lipoprotein levels.
- Genotyped apo C-II and apo E alleles.
Main Results:
- Homozygous apo C-II mutation caused complete absence of lipoprotein lipase activity.
- Heterozygous carriers showed diminished capacity to activate lipoprotein lipase.
- A wide range of lipid levels were observed in heterozygotes.
- Coinheritance of a single apo E4 allele with a single apo C-II mutation significantly increased cholesterol, triglycerides, and VLDL levels.
Conclusions:
- Apo C-II deficiency leads to severe lipoprotein lipase dysfunction.
- Lipid phenotype is influenced by interactions between apo C-II and apo E genotypes.
- Recessive genetic mutations can have interactive effects on lipid metabolism when coinherited.