中文摘要：

目的探讨中国9省（市）成年双生子BMI遗传度情况。方法收集中国双生子登记系统9省（市）成年双生子信息，采用结构方程模型计算11122对双生子BMI遗传度。结果研究对象中同卵双生子6226对，异卵双生子4896对，年龄范围25～85（39．0±10．8）岁。按地区分层，男性BMI遗传度最高的是天津，为67．8％（95％CI：50．1％。85．8％），最低的是浙江，为42．1％（95％CI：27．2％～60．9％）；女性最高的是四川，为56．2％（95％CI：47．5％．70．0％），最低的是黑龙江，为11．2％（95％CI：0—31．7％）。按性别分层，相同地区的男性BMI遗传度均高于女性，其中黑龙江男性和女性的遗传度差异最大，分别为55．3％（95％CI：35．5％～80．0％）和11．2％（95％CI：0～31．7％），而四川男性和女性的遗传度差异最小，分别为61．5％（95％CI：40．7％～86．4％）和56．2％（95％CI：47．5％～70．0％）。结论中国不同地区和不同性别人群BMI遗传度存在差别。

英文摘要：

Objective To explore the heritability of body mass index （BMI） in twins across different regions and genders in China. Methods A total of 11 122 adult twin pairs from the Chinese National Twin Registry were interviewed. A structural equation model was used to estimate the heritability of BMI. Results This study included 6 226 monozygotic twin pairs and 4 896 dizygotic twin pairs, with the age range as 25-85 （39.0± 10.8） years. Under stratified analysis by region, results showed that the highest and lowest rates on heritability of BMI in men were seen in Tianjin and Zhejiang, as 67.8% （95%CI： 50.1%-85.8%） and 42.1% （95%CI： 27.2%-60.9%）, while in women were seen in Sichuan and Heilongjiang as 56.2% （95% CI： 47.5%-70.0% ） and 11.2% （95% CI： 0.0%-31.7% ） , respectively. Results from the stratified analysis showed that, by gender, the heritability of BMI in men was higher than that in women from the same region. The biggest differences of heritability of BMI between men and women were seen in Heilongjiang as 55.3% （95%CI：35.5%-80.0%） and 11.2%（95%CI：0-3h7%）, while the smallest differences were seen in Sichuan as 61.5% （95% CI： 40.7%-86.4% ） and 56.2% （95% CI： 47.5%-70.0% ） , respectively. Conclusion The heritability of BMI across different regions and genders showed certain differences in the Chinese twins.