ASSOCIATION OF ANGIOTENSIN-CONVERTING ENZYME GENE I D POLYMORPHISM WITH CHANGE IN LEFT-VENTRICULAR MASS IN RESPONSE TO PHYSICAL-TRAINING/

Background The absence (deletion allele [D]) of a 287-base pair marker in the ACE gene is associated with higher ACE levels than its presenc e (insertion allele [I]). If renin-angiotensin systems regulate left v entricular (LV) growth, then individuals of DD genotype might show a g reater hypertrophic response than those of II genotype. We tested this hypothesis by studying exercise-induced LV hypertrophy. Methods and R esults Echocardiographically determined LV dimensions and mass (n=140) , electrocardiographically determined LV mass and frequency of LV hype rtrophy (LVH) (n=121), and plasma brain natriuretic peptide (BNP) leve ls (n=49) were compared at the start and end of a 10-week physical tra ining period in male Caucasian military recruits. Septal and posterior wall thicknesses increased with training, and LV mass increased by 18 % (all P<.0001). Response magnitude was strongly associated with ACE g enotype: mean LV mass altered by +2.0, +38.5, and +42.3 g in II, ID an d DD, respectively (P<.0001). The prevalence of electrocardiographical ly defined LVH rose significantly only among those of DD genotype (fro m 6 of 24 before training to 11 of 24 after training, P<.01). Plasma b rain natriuretic peptide levels rose by 56.0 and 11.5 pg/mL for DD and II, respectively (P<.001). Conclusions Exercise-induced LV growth in young males is strongly associated with the ACE I/D polymorphism.