介绍： 1 The biology of gender,from DNA to the brain
性别生物学——从DNA到大脑

speaker：Karissa Sanbonmatsu

00:00
So,what does it mean to be a woman?We all have XX chromosomes,right?Actually,that’s not true.Some women are mosaics.They have a mix of chromosome types with X,with XY or with XXX.If it’s not just abo...

介绍： 1 The biology of gender,from DNA to the brain
性别生物学——从DNA到大脑

speaker：Karissa Sanbonmatsu

00:00
So,what does it mean to be a woman?We all have XX chromosomes,right?Actually,that’s not true.Some women are mosaics.They have a mix of chromosome types with X,with XY or with XXX.If it’s not just about our chromosomes,then what is being a women about?Being feminine?Getting married?Having kids?You don’t have to look far to find fantastic exceptions to these rules,but we all share something that makes us women.Maybe that something is in our brains.You might have heard theories from last century about how men are better at math than women because they have bigger brains.
作为一个女人意味着什么呢？意味着我们都有XX的染色体，对吧？事实上，那不是真的。有些女性是混合质，她们的染色体为X，或XY，或XXX。如果这不仅仅是染色体的问题，那作为一个女人意味着什么？有女人味？结婚？有孩子？不用费很大力气你就能找到这些规则的绝妙例外，但我们都有一些共同之处，让我们成为女人。也许那是我们大脑里的东西。你可能听过上个世纪的理论，说男人比女人更擅长数学是因为他们的大脑更大。

00:55
These theories have been debunked.The average man has a brain about three times smaller than the average elephant,but that doesn’t mean the average man is three times dumber than an elephant...or does it?There’s a new wave of female neuroscientists that are finding important differences between female and male brains in neuron connectivity,in brain structure,in brain activity.They’re finding that the brain is like a patchwork mosaic--a mixture.Women have mostly female patches and a few male patches.With all this new data,what does it mean to be a woman?This is something that I’ve been thinking about almost my entire life.When people learn that I’m a woman who happens to be transgender,they always ask,”How do you know you’re a woman?”
这些理论已被揭穿。普通男性的大脑比大象的大脑小三倍，但这并不意味着普通男性比大象笨三倍…难道是这样?有一波新的女性神经科学家正在寻找女性和男性大脑在神经元连接、大脑结构和大脑活动方面的重要区别。他们发现大脑就像拼接嵌合体——一种混合物。女性大多有女性斑块和少数男性斑块。根据这些新数据，作为一名女人意味着什么?这几乎是我一生都在思考的问题。当人们了解到我是一个跨性别的女人时，他们总是问：“你怎么知道你是一个女人?”

01:50
As a scientist,I’m searching for a biological basis of gender.I want to understand what makes me me.New discoveries at the front edge of science are shedding light on the biomarkers that define gender.My colleagues and I in genetics,neuroscience,physiology and psychology,we’re trying to figure out exactly how gender works.These vastly different fields share a common connection--epigenetics.In epigenetics,we’re studying how DNA activity can actually radically and permanently change,even though the sequence stays the same.DNA is the long,string-like molecule that winds up inside our cells.There’s so much DNA that it actually gets tangled into these knot-like things--we’ll just call them knots.So external factors change how those DNA knots are formed.
作为一名科学家，我正在寻找性别的生物学基础。我想知道是什么让我成为现在的我。科学前沿的新发现为定义性别的生物标志物提供了线索。我和我在遗传学、神经科学、生理学和心理学方面的同事们，正在努力弄清楚性别究竟是如何起作用的。这些截然不同的领域有着共同的联系——表观遗传学。在表观遗传学中，我们正在研究DNA活动实际上是如何发生根本和永久的变化的，即使序列保持不变。DNA是一种长链状分子，缠绕在我们的细胞内。DNA如此之多，以至于它实际上会被这些类似结的东西缠结在一起——我们就叫它们结吧。所以外部因素改变了DNA结的形成。

02:55
You can think of it like this:inside our cells,there’s different contraptions building things,connecting circuits,doing all the things they need to make life happen.Here’s one that’s sort of reading the DNA and making RNA.And then this one is carrying a huge sac of neurotransmitters from one end of the brain cell to the other.Don’t they get hazard pay for this kind of work?This one is an entire molecular factory--some say it’s the secret to life.It’s call the ribosome.I’ve been studying this since 2001.One of the stunning things about our cells is that the components inside them are actually biodegradable.They dissolve,and they’re rebuilt each day,kind of like a traveling carnival where the ribes are taken down and rebuilt every single day.
你可以这样想:在我们的细胞里，有不同的装置在建造东西，连接电路，做所有它们需要的事情来让生命诞生。这是一种读取DNA并制造RNA的方法，它们带着一个巨大的神经递质囊从脑细胞的一端到另一端，难道它们做这种工作不领危险工资吗?这是一个完整的分子工厂——有人说这是生命的秘密，叫做核糖体。我从2001年就开始研究这个。我们的细胞令人惊叹的一点是，细胞内的成分实际上是可以生物降解的。它们每天都在溶解，然后重建，就像旅行嘉年华一样，肋骨每天都在拆卸和重建。