Herskind A M, McGue M, Sørensen T I, Harvald B
Centre for Health and Social Policy, Odense University, Denmark.
Int J Obes Relat Metab Disord. 1996 Feb;20(2):106-13.
To assess, by use of a population based twin register, if there are sex and age differences in genetic and environmental influences on inter-individual variation in BMI among middle-aged and elderly subjects.
Twin study.
1233 like-sex Danish twin pairs (213 MZ male, 322 DZ male, 280 MZ female, 418 DZ female pairs, age: 46-76 years, BMI: 15-45 kg/m2).
Self-reported height and weight.
Proportions of variance due to genetic and environmental factors were estimated from variance-covariance matrices using the structural equation model approach.
The most parsimonious explanation of the data was provided by a model that included additive genetic and non-shared environmental factors with the latter fixed to be equal across sex and age. The heritability of BMI was estimated to be 0.46 for males aged 46-59 years, 0.61 for males aged 60-76 years, 0.77 for females aged 46-59 years and 0.75 for females aged 60-76 years.
As in earlier studies, the present one showed a high heritability of BMI throughout adult life, with genetic influences being mainly additive and environmental influences being non-shared, without evidence for major impact of genetic dominance or shared environment. Most twin, family and adoption studies do not suggest important sex or age differences in magnitude of genetic effects, but we found that females had greater heritability than males, and that heritability in males increased by age.
利用基于人群的双胞胎登记册，评估中年和老年受试者中，遗传和环境因素对个体间BMI差异的影响是否存在性别和年龄差异。
双胞胎研究。
1233对丹麦同性双胞胎（213对同卵男性双胞胎、322对异卵男性双胞胎、280对同卵女性双胞胎、418对异卵女性双胞胎，年龄：46 - 76岁，BMI：15 - 45kg/m²）。
自我报告的身高和体重。
使用结构方程模型方法，从方差协方差矩阵估计遗传和环境因素导致的方差比例。
对数据最简洁的解释由一个模型提供，该模型包括加性遗传因素和非共享环境因素，且后者在性别和年龄上固定为相等。46 - 59岁男性的BMI遗传率估计为0.46，60 - 76岁男性为0.61，46 - 59岁女性为0.77，60 - 76岁女性为0.75。
与早期研究一样，本研究表明BMI在整个成年期都具有较高的遗传率，遗传影响主要是加性的，环境影响是非共享的，没有证据表明遗传显性或共享环境有重大影响。大多数双胞胎、家庭和收养研究并未表明遗传效应大小存在重要的性别或年龄差异，但我们发现女性的遗传率高于男性，且男性的遗传率随年龄增加。
