Objective: To examine the heritability of body mass index (BMI) and coronary heart disease (CHD), and to explore whether genetic factors can explain their correlation. Methods: Participants were from 11 provinces/municipalities reqistered in the Chinese National Twin Registry (CNTR) from 2010 to 2018. Participants data were collected from face-to-face questionnaire survey. Bivariate structure equation model was used to estimate the heritability and the genetic correlation of BMI and CHD. Results: A total of 20 340 pairs of same-sex twins aged ≥25 years were included in this study. After adjusting for age and gender, the heritability of BMI and CHD was 0.52 (95%CI: 0.49-0.55) and 0.76 (95%CI: 0.69-0.81), respectively. Further, a genetic correlation was identified between BMI and CHD (rA=0.10, 95%CI:0.02-0.17). Conclusion: In Chinese adult twin population, BMI and CHD are affected by genetic factors, and their correlation can be attributed to the common genetic basis.
目的： 评估体重指数（BMI）和冠心病的遗传度，并通过估算遗传相关性来探索二者相关的潜在机制。 方法： 以2010—2018年中国双生子登记系统在全国11个省/直辖市调查的双生子为研究对象，通过问卷调查收集研究对象的相关信息。采用双变量结构方程模型分析BMI与冠心病的遗传度，并估算其遗传相关性。 结果： 本研究共纳入20 340对年龄≥25岁的同性别双生子。调整年龄和性别后，在双变量模型中发现BMI与冠心病患病的遗传度分别为0.52（95%CI：0.49~0.55）和0.76（95%CI：0.69~0.81），而且二者具有遗传相关性，遗传相关系数rA=0.10（95%CI：0.02~0.17）。 结论： 在中国成年双生子人群中，BMI与冠心病患病均受遗传因素的影响，且二者的相关性可归因于具有共同的遗传基础。.