School of Economics, University of East Anglia, Norwich, UK.
Department of Psychiatry, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
Behav Genet. 2022 Sep;52(4-5):205-234. doi: 10.1007/s10519-022-10107-w. Epub 2022 Jul 6.
Natural selection has been documented in contemporary humans, but little is known about the mechanisms behind it. We test for natural selection through the association between 33 polygenic scores and fertility, across two generations, using data from UK Biobank (N = 409,629 British subjects with European ancestry). Consistently over time, polygenic scores that predict higher earnings, education and health also predict lower fertility. Selection effects are concentrated among lower SES groups, younger parents, people with more lifetime sexual partners, and people not living with a partner. The direction of natural selection is reversed among older parents, or after controlling for age at first live birth. These patterns are in line with the economic theory of fertility, in which earnings-increasing human capital may either increase or decrease fertility via income and substitution effects in the labour market. Studying natural selection can help us understand the genetic architecture of health outcomes: we find evidence in modern day Great Britain for multiple natural selection pressures that vary between subgroups in the direction and strength of their effects, that are strongly related to the socio-economic system, and that may contribute to health inequalities across income groups.
自然选择在当代人类中已经得到证实，但人们对其背后的机制知之甚少。我们通过使用来自 UK Biobank 的数据（409629 名具有欧洲血统的英国受试者），在两代人中，将 33 个多基因分数与生育能力进行关联，以检验自然选择。随着时间的推移，预测更高收入、教育程度和健康水平的多基因分数也预示着更低的生育率。选择效应集中在社会经济地位较低的群体、年轻的父母、性伴侣较多的人群以及没有伴侣的人群中。在老年父母或控制初次生育年龄后，自然选择的方向会发生逆转。这些模式与生育经济学理论一致，即通过劳动力市场的收入和替代效应，增加收入的人力资本可能会增加或减少生育。研究自然选择可以帮助我们了解健康结果的遗传结构：我们在现代英国发现了多种自然选择压力的证据，这些压力在方向和强度上在不同亚组之间存在差异，与社会经济制度密切相关，并可能导致不同收入群体之间的健康不平等。
