Correlation between Insertion/Deletion Polymorphism of Angiotensin I-Converting Enzyme Gene and Left Ventricular Hypertrophy

ABSTRACT

BACKGROUND: It was reported that patients who have left ventricular hypertrophy have higher D allele frequency of angiotensin I-converting enzyme gene polymorphism, especially in Caucasian normotensive men. We studied to know whether genetic polymorphism of angiotensin I-converting enzyme gene is associated with the development of left ventricular hypertrophy in Korean people whose genotype frequency is quite different from that of Caucasians. METHODS: Total 156 patients were included in this study. Presence of hypertension was checked with the criteria that hypertensives are one whose blood pressures were all above 140/90 at least 3 times spanning 2 months or one who had been diagnosed as hypertension and on his medication. Left ventricular mass index(LVMI) was calculated using electrocardiogram by Rautaharju equation, and left ventricular hypertrophy(LVH) was defined as LVMI was above 131g/m2 in male or above 110g/m2 in female. Genomic DNA was extracted from the mononuclear cell of each subjects and PCR was performed using new primers for the region of intron 16 and exon 17. RESULTS: Genotype frequencies of D/D genotype and D allele were 0.200 and 0.413 respectively in group with LVH(n=40), 0.103 and 0.392 respectively in group without LVH(n=116). There was no significant difference with each other group. However, when only the normotensives were included in this analysis, frequency of D/D genotype is significantly higher in group with LVH(0.231, n=26) than in group without LVH(0.076, n=79)(Fisher's exact test,p<0.05). There was no significant difference in genotype frequency between the normotensives(n=105) and the hypertensives(n=51). CONCLUSIONS: In Korean people, D allele of polymorphism of angiotensin I-converting enzyme gene is also associated with development of left ventricular hypertrophy in the normotensives and is not associated with essential hypertension.