Cortes Laura R, Cisternas Carla D, Forger Nancy G
Neuroscience Institute, Georgia State University, Atlanta, GA, United States.
Front Neurosci. 2019 Feb 27;13:173. doi: 10.3389/fnins.2019.00173. eCollection 2019.
The words "sex" and "gender" are often used interchangeably in common usage. In fact, the Merriam-Webster dictionary offers "sex" as the definition of gender. The authors of this review are neuroscientists, and the words "sex" and "gender" mean very different things to us: sex is based on biological factors such as sex chromosomes and gonads, whereas gender has a social component and involves differential expectations or treatment by conspecifics, based on an individual's perceived sex. While we are accustomed to thinking about "sex" and differences between males and females in epigenetic marks in the brain, we are much less used to thinking about the biological implications of gender. Nonetheless, careful consideration of the field of epigenetics leads us to conclude that gender must also leave an epigenetic imprint on the brain. Indeed, it would be strange if this were not the case, because all environmental influences of any import can epigenetically change the brain. In the following pages, we explain why there is now sufficient evidence to suggest that an epigenetic imprint for gender is a logical conclusion. We define our terms for sex, gender, and epigenetics, and describe research demonstrating sex differences in epigenetic mechanisms in the brain which, to date, is mainly based on work in non-human animals. We then give several examples of how gender, rather than sex, may cause the brain epigenome to differ in males and females, and finally consider the myriad of ways that sex and gender interact to shape gene expression in the brain.
在日常用语中，“性”和“性别”这两个词经常被互换使用。事实上，《韦氏大词典》将“性”作为性别的定义。本综述的作者是神经科学家，对我们来说，“性”和“性别”有着截然不同的含义：性基于生物因素，如性染色体和性腺，而性别具有社会成分，涉及基于个体感知到的性别的同种个体的不同期望或对待方式。虽然我们习惯于思考大脑表观遗传标记中的“性”以及男性和女性之间的差异，但我们很少会去思考性别的生物学影响。尽管如此，对表观遗传学领域的仔细思考使我们得出结论，性别也必然会在大脑中留下表观遗传印记。的确，如果不是这样那就奇怪了，因为任何重要的环境影响都能通过表观遗传改变大脑。在接下来的几页中，我们将解释为什么现在有足够的证据表明性别表观遗传印记是一个合理的结论。我们定义了性、性别和表观遗传学的术语，并描述了证明大脑表观遗传机制存在性别差异的研究，迄今为止，这些研究主要基于非人类动物的工作。然后，我们给出几个例子，说明性别而非性如何可能导致男性和女性大脑表观基因组的差异，最后考虑性和性别相互作用以塑造大脑基因表达的多种方式。
