Buisan Raül, Moriano Juan, Andirkó Alejandro, Boeckx Cedric
Universitat de Barcelona, Barcelona, Spain.
Universitat de Barcelona Institute of Complex Systems, Barcelona, Spain.
Front Cell Dev Biol. 2022 Apr 26;10:824740. doi: 10.3389/fcell.2022.824740. eCollection 2022.
Analyses of ancient DNA from extinct hominins have provided unique insights into the complex evolutionary history of , intricately related to that of the Neanderthals and the Denisovans as revealed by several instances of admixture events. These analyses have also allowed the identification of introgression deserts: genomic regions in our species that are depleted of "archaic" haplotypes. The presence of genes like in these deserts has been taken to be suggestive of brain-related functional differences between species. Here, we seek a deeper characterization of these regions and the specific expression trajectories of genes within them, taking into account signals of positive selection in our lineage. Analyzing publicly available transcriptomic data from the human brain at different developmental stages, we found that structures outside the cerebral neocortex, in particular the cerebellum, the striatum and the mediodorsal nucleus of the thalamus show the most divergent transcriptomic profiles when considering genes within large introgression deserts and under positive selection.
对已灭绝古人类的古代DNA分析，为了解人类复杂的进化史提供了独特视角，人类进化史与尼安德特人和丹尼索瓦人的进化史紧密相关，这一点已通过多次基因混合事件得以揭示。这些分析还使人们能够识别基因渗入荒漠：即我们人类基因组中缺乏“古老”单倍型的区域。这些荒漠中某些基因的存在，被认为暗示了不同物种在大脑相关功能上的差异。在此，我们寻求对这些区域及其内部基因的特定表达轨迹进行更深入的表征，同时考虑到我们人类谱系中的正选择信号。通过分析来自人类大脑不同发育阶段的公开转录组数据，我们发现，当考虑大型基因渗入荒漠中且处于正选择下的基因时，大脑新皮质之外的结构，特别是小脑、纹状体和丘脑背内侧核，显示出最具差异的转录组图谱。
