Taub Daniel R, Page Joshua
Department of Biology, Southwestern University, Georgetown TX, USA.
Department of Biology, Southwestern University, GeorgetownTX, USA; School of Medicine, Washington University, St LouisMO, USA.
Front Psychol. 2016 Jun 8;7:857. doi: 10.3389/fpsyg.2016.00857. eCollection 2016.
A large body of research has examined the behavioral and mental health consequences of polymorphisms in genes of the dopaminergic and serotonergic systems. Along with this, there has been considerable interest in the possibility that these polymorphisms have developed and/or been maintained due to the action of natural selection. Episodes of natural selection on a gene are expected to leave molecular "footprints" in the DNA sequences of the gene and adjacent genomic regions. Here we review the research literature investigating molecular signals of selection for genes of the dopaminergic and serotonergic systems. The gene SLC6A4, which codes for a serotonin transport protein, was the one gene for which there was consistent support from multiple studies for a selective episode. Positive selection on SLC6A4 appears to have been initiated ∼ 20-25,000 years ago in east Asia and possibly in Europe. There are scattered reports of molecular signals of selection for other neurotransmitter genes, but these have generally failed at replication across studies. In spite of speculation in the literature about selection on these genes, current evidence from population genomic analyses supports selectively neutral processes, such as genetic drift and population dynamics, as the principal drivers of recent evolution in dopaminergic and serotonergic genes other than SLC6A4.
大量研究探讨了多巴胺能和血清素能系统基因多态性对行为和心理健康的影响。与此同时，人们对这些多态性是否因自然选择作用而产生和/或得以维持产生了浓厚兴趣。对一个基因的自然选择事件预计会在该基因及相邻基因组区域的DNA序列中留下分子“印记”。在此，我们回顾了研究多巴胺能和血清素能系统基因选择分子信号的文献。编码血清素转运蛋白的SLC6A4基因是唯一一个得到多项研究一致支持存在选择事件的基因。对SLC6A4基因的正向选择似乎在约2万至2.5万年前始于东亚，可能也在欧洲出现。关于其他神经递质基因选择的分子信号有一些零散报道，但这些报道在不同研究中通常无法重复验证。尽管文献中有关于这些基因选择的推测，但群体基因组分析的当前证据支持遗传漂变和群体动态等选择性中性过程是SLC6A4基因以外的多巴胺能和血清素能基因近期进化的主要驱动因素。
