Oldham M C, Geschwind D H
Interdepartmental Program for Neuroscience, Department of Neurology, UCLA School of Medicine, Los Angeles, CA, USA.
Genes Brain Behav. 2006;5 Suppl 1:54-63. doi: 10.1111/j.1601-183X.2006.00195.x.
Language is a defining characteristic of our species that has emerged quite recently on an evolutionary timescale. Understanding the neurobiological substrates and genetic underpinnings of language constitutes a basic challenge for both neuroscience and genetics. The functional localization of language in the brain has been progressively refined over the last century through studies of aphasics and more recently through neuroimaging. Concurrently, structural specializations in these brain regions have been identified by virtue of their lateralization in humans and also through comparisons with homologous brain regions in non-human primate species. Comparative genomics has revealed the genome of our closest living relative, the chimpanzee, to be astonishingly similar to our own. To explore the role that changes in the regulation of gene expression have had in recent human evolution, several groups have used microarrays to compare expression levels for thousands of genes in the brain between humans and chimpanzees. By applying this approach to the increasingly refined peri-sylvian network of brain regions involved in language, it may be possible to discern functionally significant changes in gene expression that are universal among humans but unique to our species, thus casting light on the molecular basis of language in the brain.
语言是我们这个物种的一个决定性特征，在进化时间尺度上是最近才出现的。理解语言的神经生物学基础和基因基础对神经科学和遗传学来说都是一项基本挑战。在过去的一个世纪里，通过对失语症患者的研究，以及最近通过神经成像技术，语言在大脑中的功能定位得到了逐步完善。与此同时，这些脑区的结构特化已经通过它们在人类中的偏侧化以及与非人类灵长类物种同源脑区的比较而被识别出来。比较基因组学已经揭示，我们现存最近的亲属黑猩猩的基因组与我们自己的基因组惊人地相似。为了探索基因表达调控变化在人类近期进化中所起的作用，几个研究小组使用微阵列来比较人类和黑猩猩大脑中数千个基因的表达水平。通过将这种方法应用于越来越精细的与语言相关的脑区周围的颞叶周围网络，有可能辨别出基因表达中在人类中普遍存在但对我们这个物种来说独特的功能上显著的变化，从而揭示大脑中语言的分子基础。
