الفهرس Only 14 pages are availabe for public view
 |  | from | 219 |  |  |
| | | from | 219 | | |
Abstract
The progression of atherosclerosis is influenced by genetic and environmental risk factors. A number of established risk factors, such as dyslipidemia, hypertension, diabetes mellitus and smoking are significantly related to cardiovascular risk. Genetic factors may account for more than 50% of the risk for CV disease.There are only a few genetic polymorphisms clearly identified so far which contribute to premature CAD, the ApoE gene is a particularly promising candidate gene because ApoE represents an essential structural component of lipoproteins. ApoE has a storied history as a lipid transport protein and the integral association between cholesterol homeostasis and lipoprotein clearance from circulation are intimately related to ApoE’s function as a ligand for cell-surface receptors of the low-density lipoprotein receptor family.ApoE is a plasma glycoprotein and a member of the apo gene family,it is located at chromosome 19q13.2, and consists of four exons and three introns spanning 3597 nucleotides, and produces a 299 amino acid polypeptide with a molecular mass of about 34 kDa.The genetic polymorphism of ApoE results from the existence of three common co-dominant alleles (E2, E3, and E4) that code for three apolipoprotein isoforms, E2, E3, and E4, resulting in six common genotypes, E2E2, E2E3, E2E4, E3E3, E3E4, and E4E4. The most frequent isoform E3 contains a cystein at residue 112 and an arginine at residue 158,br>E2 and E4 differ from the E3 isoform in the fact that the E2 isoform contains a cystein at residue 158 and the E4 contains an arginine at residue 112.