目的　计算Graves病 (GD)的遗传度 ,讨论其临床意义。方法　调查 5 2 6例GD患者的196 8名一级亲属中GD患者数 ,根据Falconer公式计算遗传度。结果　GD遗传度为 45 % ,低于既往国内报道的结果。结论　GD的发生受遗传和环境因素的影响 ,后者的作用可能更明显 Objective To calculate the heritability of Graves disease (GD) and discuss its clinical significance. Methods The number of GD patients in 196 cases of first degree relatives from 526 GD patients was investigated. The heritability was calculated according to the Falconer formula. Results The heritability of GD was 45%, lower than the results of previous reports in China. Conclusion The occurrence of GD is affected by genetic and environmental factors, the latter may be more obvious