Angiotensinogen gene M235T polymorphism predicts left ventricular hypertrophy in endurance athletes

OBJECTIVES We studied whether left ventricular mass in athletes associates with polymorphisms in genes encoding components of the renin angiotensin sy stem. BACKGROUND Adaptive left ventricular hypertrophy is a feature of the athlet e's heart. However, similarly training athletes develop left ventricular ma ss to a different extent, suggesting that genetic factors may modulate hear t size. METHODS We measured left ventricular mass by echocardiography in 50 male an d 30 female elite endurance athletes aged 25 +/- 4 (mean +/- SD) years. Deo xyribonucleic acid samples were prepared for genotyping of angiotensinogen (AGT) gene M235T polymorphism, angiotensin-converting enzyme (ACE) gene ins ertion/deletion (I/D) polymorphism and angiotensin II type 1 receptor (AT1) gene A1166C polymorphism. RESULTS The AGT gene M235T genotypes were significantly associated with lef t ventricular mass independently of blood pressure in both genders (p = 0.0 036 for pooled data). TT homozygotes had greater mass compared with MM homo zygotes in both men (147 +/- 12 g/m vs. 132 +/- 15 g/m, p = 0.032) and wome n (121 +/- 12 g/m vs. 101 +/- 13 g/m, p = 0.019). There was a gender differ ence in the relation between myocardial mass and AGT genotype, MT heterozyg otes resembling MM homozygotes among women and TT homozygotes among men. Th e other studied gene polymorphisms were not associated with left ventricula r mass. CONCLUSIONS Angiotensinogen gene M235T polymorphism is associated with the variability in left ventricular hypertrophy induced by endurance training, with athletes homozygous for the T allele having the largest hearts. We fou nd no association between ACE gene I/D or AT1 gene A1166C polymorphisms and left ventricular mass. (C) 1999 by the American College of Cardiology.