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Apolipoprotein E polymorphism in the Tunisian population: frequency and effect on lipid parameters
1Laboratoire de Recherche LAB-SM-01, Service de Biochimie, Hôpital la Rabta, Tunis, Tunisia. jemaa_riadh@yahoo.fr
Clinical Biochemistry
|May 23, 2006
Summary
Apolipoprotein E (apo E) gene variations influence lipid levels in Tunisians, with the epsilon4 allele linked to higher cholesterol. Obesity interacts with apo E, affecting triglyceride levels and cardiovascular risk.
Area of Science:
- Genetics and Genomics
- Cardiovascular Disease Risk Factors
- Population Health Studies
Background:
- Apolipoprotein E (apo E) gene polymorphism is a key determinant of lipid metabolism.
- Understanding apo E allele frequencies and their impact on lipids is crucial for assessing cardiovascular risk in diverse populations.
Purpose of the Study:
- To determine the frequencies of apolipoprotein E (apo E) gene alleles in the Tunisian population.
- To investigate the association between apo E gene polymorphism and plasma lipid parameters.
Main Methods:
- Apo E gene polymorphism was analyzed using Polymerase Chain Reaction (PCR).
- Plasma lipid profiles, including total cholesterol, LDL-C, apo B, and triglycerides, were measured.
- The study included 122 men and 111 women aged 35–87 years.
Main Results:
- The allele frequencies were epsilon2: 7.3%, epsilon3: 84.6%, and epsilon4: 8.1%.
- Apo E polymorphism significantly impacted total cholesterol, apo B, and LDL-C levels (P<0.001).
- The epsilon4 allele was associated with higher lipid levels, while epsilon2 was linked to lower levels; triglyceride levels showed a non-significant increase with epsilon4. Obesity modified the effect of apo E on triglycerides.
Conclusions:
- The apo E allele distribution in Tunisia resembles Southern European populations, with a low prevalence of the epsilon4 allele.
- Variations in the apo E gene significantly influence plasma lipid levels.
- Gene-environment interactions, particularly with Body Mass Index (BMI), modulate the impact of apo E on lipid levels and cardiovascular risk.
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