Quagliariello Andrea, De Fanti Sara, Giuliani Cristina, Abondio Paolo, Serventi Patrizia, Sarno Stefania, Sazzini Marco, Luiselli Donata
Laboratory of Molecular Anthropology, Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, 40126, Italy; Centre for Genome Biology, Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, 40126, Italy; Human Microbiome Unit, Bambino Gesú Children's Hospital and Research Institute, IRCCS, Rome, Italy,
Laboratory of Molecular Anthropology, Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, 40126, Italy; Centre for Genome Biology, Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, 40126, Italy.
J Anthropol Sci. 2017 Dec 30;95:235-247. doi: 10.4436/JASS.95011. Epub 2017 Jul 10.
Several studies highlighted the role of climate in shaping many human evolutionary processes. This occurred even in relatively recent times, having affected various human phenotypic traits, among which metabolic processes that orchestrate absorption and accumulation of substances to maintain energy homeostasis, that is critical for the survival of individuals in high energy-expenditure environments. To date, most researches have focalized on detection of climatic influence on SNPs' frequency in populations exposed to extreme environmental conditions or by comparing variation patterns between populations from different continents. In this study, we instead explored the genetic background of distinct western European human groups at loci involved in nutritional and thermoregulation processes, to test whether patterns of differential local adaptation to environmental conditions could be appreciated also at a lower geographical scale. Taking advantage from the 1000 Genomes Project data, genetic information for 21 genes involved in nutritional and thermoregulation processes was analysed for three western European populations. The applied Anthropological Genetics methods pointed to appreciable differentiation between the examined groups especially for the PRDM16 gene. Moreover, several neutrality tests suggested that balancing selection has acted on different regions of the gene in people from Great Britain, as well as that more recent positive selection could have also targeted some PRDM16 SNPs in Finn and Italian populations. These series of adaptive footprints are plausibly related to climate variability in both ancient and relatively recent times. Since this locus is involved in thermoregulation mechanisms and adipogenesis, local adaptations mediated by a pathway related to the brown adipose tissue activity could have evolved in response to changing cold temperature exposures of such populations.
多项研究强调了气候在塑造许多人类进化过程中的作用。这种情况甚至在相对较近的时期也有发生，它影响了各种人类表型特征，其中包括协调物质吸收和积累以维持能量平衡的代谢过程，这对于个体在高能量消耗环境中的生存至关重要。迄今为止，大多数研究都集中在检测极端环境条件下人群中气候对单核苷酸多态性（SNP）频率的影响，或者通过比较不同大陆人群之间的变异模式来进行研究。在本研究中，我们转而探索参与营养和体温调节过程的基因座上不同西欧人群的遗传背景，以测试在较低地理尺度上是否也能观察到对环境条件的差异局部适应模式。利用千人基因组计划的数据，对三个西欧人群中参与营养和体温调节过程的21个基因的遗传信息进行了分析。所应用的人类遗传学方法表明，特别是对于PRDM16基因，所检测的群体之间存在明显的差异。此外，多项中性检验表明，平衡选择在英国人群中作用于该基因的不同区域，而且最近的正向选择也可能针对芬兰人和意大利人群中的一些PRDM16单核苷酸多态性。这些一系列的适应性印记可能与古代和相对较近时期的气候变异性有关。由于该基因座参与体温调节机制和成脂作用，由与棕色脂肪组织活动相关的途径介导的局部适应可能是为了应对这些人群不断变化的寒冷暴露而进化的。
