Apolipoprotein E Polymorphism and Stroke in a Population From Eastern Turkey

Abstract

Human apolipoprotein E (apo E) alleles are polymorphic with significantly different frequencies among different ethnic groups and have been associated with increased risk of coronary heart disease, and postulated as a major genetic susceptibility locus for Alzheimer's disease. Studies undertaken in different populations have shown different association patterns between apo E genotype and stroke. The aim of this study was to determine the risk of apo E genotype in stroke patients living in the eastern part of Turkey. The apo E genotypes and allele frequencies of 229 individuals from the same geographic area were determined by polymerase chain reaction and restriction fragment length polymorphism, of which 103 were patients with a documented history of stroke without other apparent dementia and 126 age-matched healthy subjects as a control group. A reduced E3=4 genotype frequency was found in subjects with stroke and the E2=3 Address correspondence to Dr. Selma DUZENLI, Ataturk University, Medical Faculty, Department of Pharmacology, 25000 Erzurum, Turkey. E-mail: selmaduzenli@hotmail.com 365 genotype frequency was elevated in patients with previous stroke. There was no association between apo E e4 allele and stroke. The APOE alleles had divergent effects in this population. Association between APOE (the gene) alleles and stroke in this population may be altered due to interaction with other genetic effects. The effects of APOE alleles and genotypes require further study in different populations.

Relationship of apoE polymorphism with lipoprotein(a), apoA, apoB and lipid levels in atherosclerotic infarct

“…We were unable to determine any association between the apoE alleles and AS in Turkish patients, as in another study from the east of Turkey [12]. However, assessment of the Hardy-Weinberg equilibrium for genotypes among controls revealed significant deviation.…”

“…Few studies have investigated apoE polymorphism in the Turkish population with stroke [12]. It was previously determined that apoE polymorphism could alter serum lipid levels, but possible alteration in Lp(a) levels in stroke patients due to apoE polymorphism has not been investigated before.…”

The genetics of stroke

“…Szolnoki and colleagues [29] also found that the presence of e4 acted synergistically with hypertension, smoking, diabetes and drinking in both large and small-vessel ischaemic stroke. However, recent studies have also showed no association [30][31][32][33].…”

“…Clearly, until further studies have E4 and smoking with stroke [28,29] No association [30][31][32][33] No association [34,35] No association with CADASIL T with stroke [57 ,58 ] No association [55,56] T with smoking and stroke [29] Factor V Leiden R506Q 0.05…”

A review of genetic causes of ischemic and hemorrhagic stroke

“…Studies on the relation between the ApoE gene ε4 polymorphism (ApoE/4) and cerebral infarction have given conflicting results. Several population-based studies, in Italy [5], Turkey [6] and Taiwan [7] have shown no association between ApoE/4 and stroke. A study in China, however, showed a 2.1-fold significantly increased risk of cerebral infarction in ApoE/4 carriers [8].…”