The corona virus disease 2019 (COVID-19) pandemic and the restrictions to reduce the spread of the virus has had a large impact on daily life. We investigated the individual differences in the effect of the COVID-19 pandemic and first lockdown on optimism and meaning in life in a sample from the Netherlands Twin Register. Participants completed surveys before (N = 9964, Mean age: 48.2, SD = 14.4) and during the first months of the pandemic (i.e. April–May 2020, N = 17,464, Mean age: 44.6 SD = 14.8), with a subsample completing both surveys (N = 6461, Mean age T1: 48.8, SD = 14.5). We applied genetic covariance structure models to twin data to investigate changes in the genetic architecture of the outcome traits due to the pandemic and the interaction of genes with the environmental exposure. Although 56% and 35% of the sample was negatively affected by the pandemic in their optimism and meaning in life, many participants were stable (32% and 43%) or even showed increased optimism and meaning in life (11% and 22%). Subgroups, specifically women, higher educated people, and people with poorer health, experienced larger negative effects. During the first months of the pandemic, slightly lower heritability estimates for optimism and meaning in life (respectively 20% and 25%) were obtained compared to pre-pandemic (respectively 26% and 32%), although confidence intervals overlap. The lower than unity genetic correlations across time (.75 and .63) suggest gene-environment interactions, where the expression of genes that influence optimism and meaning in life differs before and during the pandemic. The COVID-19 pandemic is a strong exposure that leads to imbalanced effects on the well-being of individuals. Some people decrease in well-being, while others get more optimistic and consider their lives as more meaningful during the pandemic. These differences are partly explained by individual differences in genetic sensitivity to extreme environmental change. More knowledge on the person-specific response to specific environmental variables underlying these individual differences is urgently needed to prevent further inequality.

2019 年冠状病毒病 (COVID-19) 大流行和减少病毒传播的限制措施对日常生活产生了巨大影响。我们调查了来自荷兰双胞胎登记册的样本中 COVID-19 大流行和首次封锁对生活中的乐观和意义的影响的个体差异。参与者在大流行之前（N = 9964，平均年龄：48.2，SD = 14.4）和大流行的最初几个月（即 2020 年 4 月至 5 月，N = 17,464，平均年龄：44.6 SD = 14.8）完成了调查，并完成了子样本两项调查（N = 6461，平均年龄 T1：48.8，SD = 14.5）。我们将遗传协方差结构模型应用于孪生数据，以研究由于大流行和基因与环境暴露的相互作用而导致的结果性状遗传结构的变化。尽管 56% 和 35% 的样本在乐观和生活意义方面受到了负面影响，但许多参与者保持稳定（32% 和 43%），甚至表现出对生活的乐观和意义增加（11% 和 22%） . 亚组，特别是女性、受过高等教育的人和健康状况较差的人，经历了更大的负面影响。在大流行的最初几个月，尽管置信区间重叠，但与大流行前（分别为 26% 和 32%）相比，获得的乐观和生活意义的遗传率估计值（分别为 20% 和 25%）略低。跨时间低于统一的遗传相关性（0.75 和 0.63）表明基因-环境相互作用，在大流行之前和期间，影响乐观和生活意义的基因表达不同。COVID-19 大流行是一种强烈的暴露，会导致对个人福祉的不平衡影响。一些人的幸福感下降，而另一些人则变得更加乐观，并认为在大流行期间他们的生活更有意义。这些差异的部分原因是个体对极端环境变化的遗传敏感性差异。迫切需要更多关于个体对这些个体差异背后的特定环境变量的反应的知识，以防止进一步的不平等。