Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA.
Proc Natl Acad Sci U S A. 2012 Jun 26;109 Suppl 1(Suppl 1):10709-16. doi: 10.1073/pnas.1201894109. Epub 2012 Jun 20.
The rise of comparative genomics and related technologies has added important new dimensions to the study of human evolution. Our knowledge of the genes that underwent expression changes or were targets of positive selection in human evolution is rapidly increasing, as is our knowledge of gene duplications, translocations, and deletions. It is now clear that the genetic differences between humans and chimpanzees are far more extensive than previously thought; their genomes are not 98% or 99% identical. Despite the rapid growth in our understanding of the evolution of the human genome, our understanding of the relationship between genetic changes and phenotypic changes is tenuous. This is true even for the most intensively studied gene, FOXP2, which underwent positive selection in the human terminal lineage and is thought to have played an important role in the evolution of human speech and language. In part, the difficulty of connecting genes to phenotypes reflects our generally poor knowledge of human phenotypic specializations, as well as the difficulty of interpreting the consequences of genetic changes in species that are not amenable to invasive research. On the positive side, investigations of FOXP2, along with genomewide surveys of gene-expression changes and selection-driven sequence changes, offer the opportunity for "phenotype discovery," providing clues to human phenotypic specializations that were previously unsuspected. What is more, at least some of the specializations that have been proposed are amenable to testing with noninvasive experimental techniques appropriate for the study of humans and apes.
比较基因组学和相关技术的兴起为人类进化的研究增添了重要的新维度。我们对在人类进化中经历表达变化或成为正选择靶标的基因的了解正在迅速增加，对基因重复、易位和缺失的了解也是如此。现在很明显，人类和黑猩猩之间的遗传差异比以前想象的要广泛得多；它们的基因组并非 98%或 99%相同。尽管我们对人类基因组进化的理解迅速增长，但我们对遗传变化与表型变化之间关系的理解仍然很薄弱。即使是研究最深入的基因 FOXP2 也是如此，该基因在人类末端谱系中经历了正选择，被认为在人类言语和语言的进化中发挥了重要作用。部分原因是，将基因与表型联系起来的困难反映了我们对人类表型特化的普遍了解不足，以及解释在无法进行侵入性研究的物种中遗传变化后果的困难。从积极的方面来看，对 FOXP2 的研究，以及对基因表达变化和选择驱动的序列变化的全基因组调查，为“表型发现”提供了机会，为以前未被怀疑的人类表型特化提供了线索。更重要的是，至少已经提出的一些特化是可以用适合人类和猿类研究的非侵入性实验技术来测试的。
