Genome–Environment Coordination in Neurobehavioral Development

Abstract

How do we become who we are? Are we tabula rasa, blank slates randomly scrambling for imprintation of information, or are we merely the constructions of our selfish genetic blueprints? Current scientific philosophy tells us we are neither preprogrammed nor do we possess unadulterated free will. While mammalian neurobehavioral development is biologically constrained, it is also sensitive to experience. Neurophysiological patterning guides motivation and emotion that we use to navigate our environments. Our environments, however, often present unexpected challenges. We develop our strategies for responding to stress throughout prenatal and postnatal development. How does this neurobehavioral development unfold? It proceeds according to exceedingly elegant and precisely timed interactions between the genome and the environment. These interactions begin at conception and may last a lifetime but may be particularly potent at critical periods in development. During these critical periods of embryonic and early postnatal development, even the slightest variability in the coordination between the genome and the environment results in some of the breathtaking neurobehavioral variability in stress adaptation we observe in infant mammals. This chapter will examine some examples of genome– environment coordination that impacts prenatal and early postnatal neurobehavioral development in nonhuman primates. I will discuss how certain regions of the genome may put individuals at risk for disadvantageous neurobehavioral development following early stress and possible mechanisms for how this risk may occur. Next I will introduce the reader to the diverse role of epigenetics in the effects of early environment. Finally, I will consider the potential consequences of gene–environment coordination across generations. The goal of this chapter is to provide examples of the complexity of the inheritance and development of stress response strategies and to highlight new avenues for understanding why some nonhuman primates wither when challenged, while others thrive.