Tarnoki Adam D, Szalontai Laszlo, Fagnani Corrado, Tarnoki David L, Lucatelli Pierleone, Maurovich-Horvat Pal, Jermendy Adam L, Kovacs Attila, Molnar Andrea Agnes, Godor Erika, Fejer Bence, Hernyes Anita, Cirelli Carlo, Fanelli Fabrizio, Farina Filippo, Baracchini Claudio, Meneghetti Giorgio, Gyarmathy Anna V, Jermendy Gyorgy, Merkely Bela, Pucci Giacomo, Schillaci Giuseppe, Stazi Maria A, Medda Emanuela
Department of Radiology, Semmelweis University, 78/a Ulloi street, H-1082 Budapest, Hungary.
Hungarian Twin Registry, 29 Erdélyi street, 1212 Budapest, Hungary.
Cardiol J. 2021;28(3):431-438. doi: 10.5603/CJ.a2019.0089. Epub 2019 Sep 6.
Heart rate (HR), mean arterial pressure (MAP) and carotid intima-media thickness (cIMT) are moderately heritable cardiovascular traits, but the environmental effects on the longitudinal change of their heritability have never been investigated.
368 Italian and Hungarian twins (107 monozygotic, 77 dizygotic) underwent oscillometric measurement and B-mode sonography of bilateral carotid arteries in 2009/2010 and 2014. Within- -individual/cross-study wave, cross-twin/within-study wave and cross-twin/cross-study wave correlations were estimated, and bivariate Cholesky models were fitted to decompose the total variance at each wave and covariance between study waves into additive genetic, shared and unique environmental components.
For each trait, a moderate longitudinal stability was observed, with within-individual/crosswave correlations of 0.42 (95% CI: 0.33-0.51) for HR, 0.34 (95% CI: 0.24-0.43) for MAP, and 0.23 (95% CI: 0.12-0.33) for cIMT. Cross-twin/cross-wave correlations in monozygotic pairs were all significant and substantially higher than the corresponding dizygotic correlations. Genetic continuity was the main source of longitudinal stability, with across-time genetic correlations of 0.52 (95% CI: 0.29-0.71) for HR, 0.56 (95% CI: 0.31-0.81) for MAP, and 0.36 (95% CI: 0.07-0.64) for cIMT. Overlapping genetic factors explained respectively 57%, 77%, and 68% of the longitudinal covariance of the HR, MAP and cIMT traits.
Genetic factors have a substantial role in the longitudinal change of HR, MAP and cIMT; however, the influence of unique environmental factors remains relevant. Further studies should better elucidate whether epigenetic mechanisms have a role in influencing the stability of the investigated traits over time.
心率（HR）、平均动脉压（MAP）和颈动脉内膜中层厚度（cIMT）是具有中度遗传性的心血管特征，但环境因素对其遗传性纵向变化的影响尚未得到研究。
2009/2010年和2014年，368名意大利和匈牙利双胞胎（107对同卵双胞胎，77对异卵双胞胎）接受了示波测量和双侧颈动脉B型超声检查。估计个体内/跨研究波、跨双胞胎/研究内波和跨双胞胎/跨研究波的相关性，并拟合双变量Cholesky模型，将各波的总方差和研究波之间的协方差分解为加性遗传、共享和独特环境成分。
对于每个特征，观察到中度的纵向稳定性，HR的个体内/跨波相关性为0.42（95%CI：0.33-0.51），MAP为0.34（95%CI：0.24-0.43），cIMT为0.23（95%CI：0.12-0.33）。同卵双胞胎对中的跨双胞胎/跨波相关性均显著，且明显高于相应的异卵双胞胎相关性。遗传连续性是纵向稳定性的主要来源，HR的跨时间遗传相关性为0.52（95%CI：0.29-0.71），MAP为0.56（95%CI：0.31-0.81），cIMT为0.36（95%CI：0.07-0.64）。重叠的遗传因素分别解释了HR、MAP和cIMT特征纵向协方差的57%、77%和68%。
遗传因素在HR、MAP和cIMT的纵向变化中起重要作用；然而，独特环境因素的影响仍然显著。进一步的研究应更好地阐明表观遗传机制是否在影响所研究特征随时间的稳定性方面发挥作用。
