DNA Polymorphisms and Haplotypes of Apolipoprotein A5's Attribution to the Plasma Triglyceride Levels in Koreans

PURPOSE: Recent studies using human and mice reported that apolipoprotein A-V (APOA5) gene plays an important role in controlling triglyceride (TG) concentrations. The purpose of the present study was to investigate the correlation between single nucleotide polymorphisms (SNPs) and haplotypes in the APOA5 gene and TG in subjects and to search for possible associations of the APOA5 gene variants and common haplotypes with hypertriglyceridemia (HTG). MATERIALS AND METHODS: We examined the case-control subjects including 100 HTG patients and 243 unrelated healthy control. The genes were screened for SNPs by direct sequencing in 48 genetically unrelated individuals. Six SNPs (-1390C>T, -1020G>A, -3A>G, V150M, G182C and 1259T>C) were genotyped in case and control populations. RESULTS: In this study, our results indicated a strong association between APOA5 SNP -3A>G and G182C and elevated TG levels (p<0.001). Analysis of the SNPs from APOA5 gene has identified major haplotype showing very strong association with HTG, CGGGTT (p<0.001). Likelihood ratio test (LRT) of these six SNPs revealed that haplotypes were strong independent predictors of HTG (p<0.001). Haplotype-trend logistic regression (HTR) analysis revealed a significant association between the CGGGGC (haplotype 2) and CGGGTT (haplotype 4) and HTG (OR=2.48, 95% CI=1.06-5.76 and OR=8.54, 95% CI=2.66-27.42, respectively). CONCLUSION: We confirm that the APOA5 variants are associated with triglyceride levels and the haplotype may be strong independent predictors of HTG among Koreans.

An Insertion/Deletion Polymorphism in the alpha(2B)-Adrenoceptor Gene is not a Genetic Risk Factor for Coronary Artery Disease in the Korean Population

BACKGROUND AND OBJECTIVES: Cardiovascular disease (CVD) is a complex multigenic disorder, with significant inheritable elements having important roles relating to environmental factors. Recently, the alpha 2 adrenoceptor (alpha(2)-AR) gene has been reported to be involved in the development of coronary artery disease (CAD). The aim of this study was to investigate the relationships between an insertion/deletion (I/D) in alpha(2B)-AR and CAD in Korean subjects. SUBJECTS AND METHODS: The alpha(2B)-AR I/D polymorphism, which was located in the third intracellular loop of the receptor polypeptide, was examined in 292 patients (M:F=219:73) with CAD and 151 healthy control subjects (M:F=70:81) who visited the Cardiovascular Genome Center in Yonsei Cardiovascular Hospital. RESULTS: In the patient group, 77 men (35.1%) and 26 women (35.6%) had the I/I genotype; 105 men (47.9%) and 39 women (53.4%) a heterozygous genotype and 37 (17.0%) and 8 (11.0%) the D/D genotype. In the controls, 23 men (32.8%) and 29 women (35.8%) had the I/I genotype; 38 (54.3%) and 39 (48.1%) the I/D genotype and 9 (12.9%) and 13 (16.1%) the D/D genotype. There were no differences in the genotype frequencies between the patient and control groups, either in men or women. From a logistical regression analysis, the alpha(2B)-AR genotype was not significantly associated with CAD in our study group. CONCLUSION: The alpha(2B)-AR I/D polymorphism is not a risk factor for CAD in the Korean population.