Department of Physiology Faculty of Biology, University of Murcia, Murcia, Spain.
IMIB-Arrixaca, Murcia, Spain.
Sci Rep. 2017 Sep 26;7(1):12340. doi: 10.1038/s41598-017-12460-x.
Siesta is a relevant aspect of sleep due to its posited relationship with health or cognitive function. However, unlike night-time sleep, studies about daytime-sleep determinants and characteristics are scarce, and the genetic/environmental structure of siesta is still unknown. Our aim was to explore the relative contribution of genetic and environmental factors to variation in sleep-wake rhythm, measured by a continuous assessment of temperature-activity-position (TAP), which allows for diurnal sleep analysis. The sample comprised 53 pairs of female twins (28 MZ and 25 DZ), selected from the Murcia Twin Register. Mean age of participants was 52 (SD: 6.03). Zygosity was determined by DNA. We conducted separate univariate analyses to study the sources of variance of daytime and night-time sleep parameters. About 60% of the sample reported to take siesta at least once a week. Heritability of taking siesta and daytime sleep duration was 65 and 61% respectively. Other sleep parameters obtained by TAP showed heritability estimates between 36 and 69%, suggesting a relevant impact of genetic factors on sleep rhythm. This is the first study to investigate the relative contribution of genetic factors to siesta. By using TAP, we introduce a novel approach to the study of diurnal sleep characteristics.
午睡是睡眠的一个重要方面，因为它与健康或认知功能有关。然而，与夜间睡眠不同，关于日间睡眠决定因素和特征的研究很少，午睡的遗传/环境结构仍不清楚。我们的目的是探索遗传和环境因素对睡眠-觉醒节律变化的相对贡献，这是通过对温度-活动-位置（TAP）的连续评估来衡量的，TAP 允许对日间睡眠进行分析。该样本包括来自穆尔西亚双胞胎登记处的 53 对女性双胞胎（28 对同卵双胞胎和 25 对异卵双胞胎），参与者的平均年龄为 52 岁（SD：6.03）。通过 DNA 确定了同卵双生子和异卵双生子的类型。我们进行了单独的单变量分析，以研究日间和夜间睡眠参数的方差来源。大约 60%的样本报告每周至少有一次午睡。午睡和日间睡眠时间的遗传率分别为 65%和 61%。通过 TAP 获得的其他睡眠参数的遗传率估计在 36%至 69%之间，这表明遗传因素对睡眠节律有重要影响。这是第一项研究遗传因素对午睡相对贡献的研究。通过使用 TAP，我们为日间睡眠特征的研究引入了一种新方法。
