Sunde Hans Fredrik, Eilertsen Espen Moen, Torvik Fartein Ask
Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway.
PROMENTA Research Centre, Department of Psychology, University of Oslo, Oslo, Norway.
Nat Commun. 2025 Jun 6;16(1):5264. doi: 10.1038/s41467-025-60483-0.
We develop a framework for understanding indirect assortative mating and provide updated definitions of key terms. We then develop family models that use partners of twins and siblings to freely estimate the degree of genetic and social homogamy, and account for it when investigating sources of parent-offspring similarity. We applied the models to educational attainment using 1,545,444 individuals in 212,070 extended families in the Norwegian population and Norwegian Twin Registry. Partner similarity in education was better explained by indirect assortment than direct assortment on observed educational attainment, with social homogamy being particularly important. The implied genotypic partner correlation (r = 0.34) was comparable to earlier studies, and higher than expected under direct assortment. About 38% of the parent-offspring correlation (r = 0.34) was attributable to various forms of environmental transmission. Alternative models that assumed direct assortment estimated environmental transmission to be lower, but these did not fit the data well.
我们开发了一个用于理解间接选型交配的框架，并提供了关键术语的更新定义。然后，我们构建了家族模型，利用双胞胎和兄弟姐妹的配偶来自由估计遗传和社会同质性的程度，并在研究亲子相似性的来源时加以考虑。我们将这些模型应用于挪威人口和挪威双胞胎登记处的212,070个大家庭中的1,545,444个人的教育程度。在观察到的教育程度上，间接选型比直接选型能更好地解释配偶在教育方面的相似性，其中社会同质性尤为重要。隐含的基因型配偶相关性（r = 0.34）与早期研究相当，且高于直接选型下的预期。约38%的亲子相关性（r = 0.34）可归因于各种形式的环境传递。假设直接选型的替代模型估计环境传递较低，但这些模型与数据拟合不佳。
