Department of Economics, National University of Singapore Singapore.
Front Hum Neurosci. 2013 May 14;7:195. doi: 10.3389/fnhum.2013.00195. eCollection 2013.
Human beings are an extraordinarily altruistic species often willing to help strangers at a considerable cost (sometimes life itself) to themselves. But as Darwin noted "… he who was ready to sacrifice his life, as many a savage has been, rather than betray his comrades, would often leave no offspring to inherit his noble nature." Hence, this is the paradox of altruism. Twin studies have shown that altruism and other prosocial behavior show considerable heritability and more recently a number of candidate genes have been identified with this phenotype. Among these first provisional findings are genes encoding elements of dopaminergic transmission. In this article we will review the evidence for the involvement of one of these, the dopamine D4 receptor (DRD4) gene, in shaping human prosocial behavior and consider the methodologies employed in measuring this trait, specific molecular genetic findings and finally, evidence from several Gene × Environment (G × E) studies that imply differential susceptibility of this gene to environmental influences.
人类是一种非常利他的物种，常常愿意以相当大的代价（有时甚至是生命本身）来帮助陌生人。但是正如达尔文所指出的：“……许多野蛮人宁愿牺牲自己的生命，也不愿背叛自己的同伴，因此他们往往没有后代来继承他们高尚的天性。”因此，这就是利他主义的悖论。双胞胎研究表明，利他主义和其他亲社会行为表现出相当大的遗传性，最近又确定了一些候选基因与这种表型有关。其中一些初步发现的基因编码多巴胺能传递的元素。在本文中，我们将回顾涉及其中之一的多巴胺 D4 受体（DRD4）基因在塑造人类亲社会行为中的证据，并考虑用于测量这种特征的方法、特定的分子遗传学发现以及来自几项基因-环境（G×E）研究的证据，这些证据表明该基因对环境影响的敏感性存在差异。
