性染色体的诡异历史
日期:2020-08-27 15:08

(单词翻译:单击)

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OK. So we are going to start in 1891, when a German scientist was looking through a microscope at insect cells.
好的。我们要从1891年讲起,那时一位德国科学家正在用显微镜观察昆虫细胞。
And he saw something kind of funny.
他看到了一些有意思的东西。
At the center of the cells, there was this dark stuff. No one had ever seen it before.
在细胞的中心,有个暗色的东西。之前从来没有人注意过。
And he noticed that as the cells would multiply and divide, it would go into some of the new cells but not the others.
他观察到当细胞分裂增殖时,这个东西就会进入一些新细胞,但其他细胞中却没有。
He didn't know what it was, so he gave it a really great name. He called it the "X element."
他不知道这是什么,便给它起了一个好名字。他称之为“X元素”。
And he was like, "We'll just fill in that X later."
他的意思是,“我们到时候再把这个X填上就好。”
And then, fast-forward 10 years later, and there is an American scientist,
接着,快进十年后,有一位美国科学家,
and she is looking through her microscope, also at insect cells.
她也用她的显微镜去观察昆虫细胞。
And she sees something funny. There's more of this dark stuff.
然后,她看到了一些有趣的东西,有更多这种暗色的东西。
And it's kind of tiny, it's hanging out near the X element.
而它们挺小的,就在X元素的附近。
And eventually, someone was like, "Well, if that one thing's called X, should we call this other thing Y?"
最后,有人说,“好吧,既然这里有一个X,那么这个我们就叫Y吧?”
And like that, the sex chromosomes had been discovered.
就这样,人们发现了性染色体。
So chromosomes, you probably all know what they are, but I will tell you anyways.
染色体,你们或许知道它们是什么,但我还是要告诉你们。
They're made up of DNA -- everything has it, it's the blueprint of life,
它们由DNA组成--一切事物都有DNA,它是组成生命的蓝图,
we've got rats, we've got trees, we've got insects, we've got humans.
无论老鼠、树木、昆虫,还是人类都有。
And in the case of human chromosomes, geneticist Melissa Wilson broke it down for me like this.
对于人类染色体而言,遗传学家梅丽莎·威尔逊是这么解释的。
Typically, you'll get one copy of every chromosome from your genetic mom and one copy of every chromosome from your genetic dad,
通常,你会从生母的身上遗传她的染色体复本,同时,你也会遗传生父染色体的复本,
and we have 22 of these that you get one copy from mom and one copy from dad. And then there's a 23rd pair, X and Y.
于是我们拥有的22条染色体,一半来自母亲,一半来自父亲。然后存在的第23对,就是X和Y。
So while all the other chromosomes are numbered, one through 22, we do not call X and Y 23.
所以当其他的染色体都从1到22标号的时候,我们不把X和Y这对叫成23。
I like to think that they are waiting for, like, a LeBron James to come along.
我喜欢把它们当成在等待勒布朗·詹姆斯的到来。
But in this instance, they were like, "We're just going to keep the letters, and then we'll give them a title."
但是在这个情况下,他们说,“我们就继续保留这俩字母,然后为这两个字母命名。”
They called them the sex chromosomes.
他们将这对命名为性染色体。
Now I would wager that in the United States, these are the most well-known chromosomes for one simple fact:
我敢说,它们是全美国最出名的染色体,因为显而易见:
that we say X equals "girl," and Y equals "boy" -- that they are responsible for sex.
我们将X等同于女孩,而Y则等同于男孩--意味着性染色体和性别相关。
And -- and I had to learn this -- but when I'm talking about "sex" here,
我必须要申明--当我在这说到“性”的时候,
I'm talking about the way biology gives us gonads, which are our ovaries and our testes
我指的生物学上赋予我们性腺的方式,指卵巢和睾丸,
I'm not talking about gender, which is how we identify.
我不是在说人类概念中我们所认定的性别。
And so, as a reporter at the show -- "Radiolab," the audio documentary program I work for
所以,作为一个在“Radiolab“工作的有声纪录节目的记者,
I was like, what's up with these sex chromosomes?
我很好奇,这些性染色体是怎么回事?
You know, that's kind of my job, I think things are weird,
毕竟这是我工作的一部分,当我发现了一些怪事,
and then I get to call people about them and ask questions, and then hopefully they answer.
我就会去咨询相关的专家,提出问题且希望能找到答案。
And in this case, a lot of people answered.
在这种情况下,大多数人做出了回答。
And in the two years I had of reporting on X and Y, as part of "Gonads,"
两年中,我一直在报道作为性腺一部分的X和Y染色体,
the series on sex and gender I ended up doing for "Radiolab,"
我最后为“Radiolab”做了这个性与性别系列节目。
I found out that these two chromosomes live in a world that is unexpected, a little unsettling;
我发现这两条染色体生活在一个意想不到的世界,且有些混乱,
where things that I thought were facts were, like, twisted in ways I hadn't seen before.
我认为是事实的事情却像是以我从没见过的方式扭曲的。
And the world goes so far beyond the boundaries of sex, I was like, "Maybe we should all talk about this."
这个世界已远远超越性的边界,我想,“也许我们应该认真讨论一下这些事。”
So, you're you all, we're all going to talk about it.
所以,既然你们都在这里,我们不妨一起讨论一下这个事情。
And for me, the true story of X and Y starts with their name.
对于我来说,X和Y的真实故事始于它们的名字。
So within years of being discovered, these two little chromosomes had acquired more than 10 different names.
在发现它们的头几年里,这两条小小的染色体起码被起了10个不同的名字。
There was diplosome and heterochromosome and idiochromosome,
有“双质体”和“异染色体”,还有“副染色体”,
and most of the names had to do with their structure, their shape, their size.
而且大部分的名字都基于它们的结构、形状,还有大小。
And then there was "sex chromosome," which they had been given because of the fact that we had started seeing that
然后就有了根据事实所命名的“性染色体”,我们开始意识到,
the X would go with the females, and the Y would often go with the males.
女性携带着X染色体,而男性携带着Y染色体。
But scientists were like, "Do we really want to call them sex chromosomes?"
但科学家觉得,“我们真的要叫它们性染色体吗?”
And science historian Sarah Richardson is the one who told me this story.
科学历史学家莎拉·理查森告诉了我这个故事。
For three decades, scientists were like, "You should not call them the sex chromosomes.
三十年来,科学家们都觉得,“你不可以叫它们性染色体。
The X and Y have many functions, and you wouldn't assume that a single chromosome controls a single trait.
因为这个X和Y还有许多功能,而且你不会认为一条染色体只控制一个单一特征。
Imagine calling one chromosome the 'urogenital chromosome,' or the 'liver chromosome.'"
想想如果我们叫一个染色体“泌尿生殖染色体”,或者“肝脏染色体”会如何。”
Scientists, if you dig into the history -- it's really cool, you should
科学家们,如果你去挖掘历史的话--这真的很酷,你应该去探索一下,
were hesitant to, like, commit to such a specific name and such a powerfully connotated name.
就不会对这个特定且有强烈暗示的名字有所犹豫。
There was a fear that it would actually be really limiting -- maybe to science, maybe to society -- but the fear was in the room.
人们担心这个名字会带来限制--可能限制科学,限制社会,这个担心是确实存在的。
And you can see they ended up getting "sex chromosome" -- it's like a pretty juicy title, it popularized genetics, you know?
我们知道,他们最终敲定了“性染色体”这个名字--一个很形象生动的名字,向人们普及了遗传学。
But in the 100-year history since we settled on that name, you can see it starts to get a little complicated.
但是自从我们确定了这个名字后的100年里,事情开始变得有点复杂。
So around 1960 -- this is going to be our first stop on the complicated world of the sex chromosomes
在大概在1960年的时候,这是我们在染色体的复杂世界中的第一站,
so around 1960, we had discovered that you could be XYY. They discovered an XYY man.
大约在1960年,我们发现了人类性染色体可以是XYY。他们发现了一个有XYY染色体组合的男性。
And to digress a little here, it turns out that the model of "X equals girl and Y equals boy" is really simplistic.
这里离题一下,其实,“X等同女孩,Y等同男孩”的模型过于简单化了。
You can actually be a whole bunch of different combinations of X and Y, giving you, like, different types of biological sex.
实际上你可以是一堆X和一堆Y的组合体,赋予你生物学上不同的性别。
You could be two Xs and two Ys together. You could be four Xs, you could be five Xs, you could be XO.
你可以是两个X和两个Y组合在一起,也可以是四个X,或者五个X。甚至是XO。
And so I thought that was pretty crazy, because I was like,
这真是太玄幻了,因为我心想:
"Wow, this really upends a model of biological sex I think most of us in this room have been taught."
“哇哦,这真的颠覆了我们这里大多数人所学的生理性别知识。”
So a few years after they realized that you can be XYY, researchers go to a prison in Scotland,
当人们意识到你的性别可以是XYY的几年后,有研究者们去了一间位于苏格兰的监狱,
and they do genetic analysis of a bunch of the male prisoners.
对一群男性囚犯进行了基因分析。
And they find a number of people who are XYY. And according to Sarah:
然后他们发现有相当数量的人是XYY的组合。根据莎拉所说:
They just rushed to publish a theory suggesting that this extra Y chromosome could explain criminality in some men.
他们急于发表一套理论,猜想那个多余的Y染色体与部分男性的暴力行为相关。
Yeah. So the logic goes like this: By this point, we're thinking Y is male.
就是这样。所以逻辑是:这个时候,我们认为Y代表着男性。
We think male is aggressive, so Y must be aggression.
而男性是具有较强侵略性,所以Y一定是侵害相关的染色体。
If you've got an extra Y, you must be crazy. And like, we went nuts with this theory.
如果你有一个额外的Y,你肯定会变得很狂躁。就这样,我们对这个理论产生了很盲目的痴迷。
We called it the supermale, they started scanning more prisoners, serial killers, boys.
我们管这类基因叫超级男性,研究者们开始扩大分析样本,包括杀人狂魔,男孩们。
And in all seriousness, there was actually a suggestion that we consider aborting XYY fetuses.
这件事严肃到,当时有人建议孕妇打掉基因组合为XYY的胎儿。
So in 1980, this theory pretty much toppled, for a number of reasons.
但在1980年,这个理论因为种种原因被推翻了。
One, there had been this really large study that basically showed there was no connection between Y and violence,
其中一个原因是,当时有一个非常大型的研究,大体上没有得出理论中Y和暴力相关的推断。
I think we all saw that coming. And then, there was one other thing.
我想我们都预料到了。还有一件事。

性染色体的诡异历史

Going back and looking at those original findings in that high-security psychiatric institution,
回溯那些保存于高戒严精神病院的最初发现,
they had also found a high number of individuals with an extra X chromosome. So these are XXY, as opposed to XYY. Really?
当时人们同样发现了大数量的个体拥有额外的X染色体。像XYY一样,也存在对应的XXY。真的吗?
Yeah. Now, they never claimed that the individuals with an extra X chromosome were superfemales.
是的,但是他们从来没有发出过声明,将有额外的X染色体的个体称为超级女性。
They never investigated whether they had higher rates of violence.
他们也从未调查过她们是否有高暴力率。
Seems like kind of an oversight. I don't know.
这看起来像一种疏忽。谁知道呢?
But I think it's interesting, because what you see is if you start looking at these chromosomes through the lens of sex,
但是我觉得这很有意思,因为你会发现,一旦你开始透过性的镜头去观察这些性染色体的时候,
what naturally falls in place behind is we look at them through the lens of gender, and the traits that we associate with gender.
我们才是那个自然而然落后的,因为我们在用带性别以及性别相关特征的眼镜去看待这个事物。
So men were violent, and Y explained why they were in prison.
于是我们认为男人就是暴力的,Y染色体解释他们为什么进了监狱。
The X did not do that, because like, you know, what's X? We don't associate it with violence.
然而X染色体并不会这样,因为,你懂的,X代表了什么?我们不会把暴力和X联系在一起。
And while we don't believe in supermales today -- God, I hope we don't -- we don't believe in supermales today,
虽然今天我们不相信有超级男性--上帝呀,我希望我们不会--不会相信现今有超级男性,
there is a very similar conversation that's still happening around inherent violence in boys and biology.
类似的对话仍发生在关于男性与生俱来的暴力和生物学讨论中。
So my next stop on the weird world of X and Y, or things feeling a little topsy-turvy, is 1985.
所以我在这个X和Y的诡异世界,或者说关于这个混乱事件的调查的下一站是在1985年。
The World University Games were set to happen in Japan, and the Spanish hurdler María José Martínez-Patino was scheduled to run.
那一年,世界大学生运动会如期在日本举行,西班牙跨栏运动员玛丽亚·何塞·马丁内斯-帕蒂诺计划参加比赛。
She was like a hot shot, a rising superstar. And the night before her race, they had her DNA scanned.
她就是一个冉冉升起的耀眼新星。而在比赛的前夜,他们检测了她的DNA。
Now at the time, this was a thing that they were doing, because they were like,
在当时,他们会做这个事是因为他们会想:
"OK, we don't want men covertly racing as women, so we're going to scan the women and make sure all their Xs line up."
“我们可不想让一个男人像女人一样偷偷摸摸地比赛,所以我们检测女性运动员,确保她们的染色体都是X,她们的确是女性。”
And so I heard this story from Ruth Padawer who was a New York Times Magazine reporter and she reported on María.
我是在露丝·帕达沃那得知了这个故事,她曾经是《纽约时报》杂志的的记者,而且当时她报道了玛丽亚的故事。
So they tell her the chromosome test results were abnormal.
工作人员告诉玛丽亚,她的染色体检测结果不正常的。
Although on the outside, she was fully female, she had XY chromosomes and these internal testes.
虽然从外表上看,她完全就是个女人,但她有XY染色体和隐性睾丸。
They were like, "We hate to break it to you, María, but you're actually a dude. You can't race with the ladies."
他们是这样说的,“我们不想打击你,但是玛丽亚,你是一个货真价实的男人。你不可以和女性们一起比赛。”
And so she's thrown off the national team, she's expelled from the athletics residence, she's denied her scholarship,
然后她就这样被踢出了国家队,在体育竞技中失去了席位,她的奖学金被取消,
a bunch of her friends dump her, fellow athletes abandon her, she loses her medals, her records are revoked.
一些朋友远离了她,运动员同行抛弃了她,她失去了她的奖牌,她的比赛记录也被撤销。
So it turns out -- remember when I told you you can be a bunch of different combinations of X and Y
结果是,像我刚说的,你可以拥有一堆XY的组合体,
you can also be XY and be female. You can be XX and male.
你可以也同时有XY并且是女性,或者你可以有XX但是男性。
In María's case, she was something called androgen insensitive.
在玛丽亚的事件中,她属于对雄激素不敏感的情况。
Which means that she did have some sort of internal testes -- they were making testosterone -- but her body couldn't use it.
意味着她确实有隐性睾丸--这些睾丸会产生一些睾酮素,但是她的身体是用不了的。
And so if you thought of testosterone as, like, a superpower, she was not benefiting from it.
所以如果你觉得睾酮素是什么大力菠菜的话,玛丽亚对这个免疫。
And so eventually, sports authorities, like, let her back in, but her career was done.
所以最终,体育当局同意她归队,但是她的职业生涯已经结束了。
And in this instance you see how, if you assign sex to a specific place in the body, or at least, like, this is what I saw, right?
在这个案例中,你可以知道,如果你把性归属于身体的某个部位,至少这是我所看到的。
If you assign sex to a specific place in the body, it somehow makes us think that we can go into a body,
如果你把性这个概念具化为身体的某个部位,它就会在某种程度上让我们以为我们可以探究人体,
look at a specific place and tell someone we know something more about them than they know about themselves.
通过观察某个特定的部位,告诉别人我们比他们自己更了解他们。
And that feels terrifying to me. And we don't genetically test female athletes anymore,
这让我觉得很可怕。当然了,我们已经不再对女运动员进行基因检测了。
but you can see very similar conversations happening when we talk about testosterone in sports,
但是当我们讨论睾酮素对体育运动的作用时,你仍然可以听到类似的话题,
you can also see it in suggestions that we take transgender individuals and we genetically analyze them and we tell them who they are.
你也可以看到有人建议我们接纳变性人,我们在基因层面上检测他们,然后揭晓他们的真实性别。
That is real, that is a conversation that has happened recently.
这是真的,这是最近发生的讨论。
The last place that I'll share with you where these chromosomes got complicated for me is this one thing that Melissa told me.
我要和你们分享的最后一件事是,在我看来,这些染色体在哪里变得复杂了,这是梅丽莎告诉我的一件事情。
You can't survive without an X chromosome.
离开了X染色体,你将无法存活。
No matter your gonads, no matter your identity, every single human being has to have an X chromosome,
无论你拥有什么样的性腺和特质,每一个人类必须要有一个X染色体,
because without one, the rest of your body doesn't develop.
如果没有的话,你的身体就无法发育。
Why do we call this the female chromosome?
那为什么我们要将X称呼为女性染色体?
OK, this is something I had never though about,
好吧,这是我从来没有想过的事情,
but literally, every single person in this audience has an X chromosome, I'm not lying.
但不夸张地说,在场每位观众都有X染色体,我没骗你们。
Every single person on the planet has an X chromosome, but no one is going around like, "This is the every-person chromosome."
这个星球上的每一个人都有一条X染色体,但是却没有人说,“这是一个全人类染色体”。
You know? Like, somehow it's over here, the Y is over there, and they must be really different,
对吧?毕竟可以这么说,X在这边,Y在这边,而且它们肯定是不同的,
and I'm just like, it would be so much better if it was the every-person chromosome.
而我认为如果称它们为全人类染色体会更好。
And not just because I'm like, love you all and I want you all in,
不仅仅因为,比如说我爱你们,所以希望你们都有这个染色体,
but because of what we're overlooking by the fact that we consider it female.
而是因为我们忽略了大家总认定它是女性染色体的事实。
Because I'm going to tell you one of the craziest things I found out.
因此,接下来我要告诉大家我发现的最玄幻的一个事实。
Which is, when you think about the X chromosome, of the almost 1,100 genes on the X chromosome,
那就是,当你在思考X染色体时,在这个染色体上的1100个基因里,
how many do you think have to do with sex and reproduction? Like, get a number in your head.
你觉得有多少基因与性和繁殖有关?现在,你在脑海里猜一个数字。
Four percent. That means 96 percent of the rest of that chromosome is doing something that has nothing to do with your gonads.
百分之四。这意味着剩下的百分之九十六和你的性腺一点关系都没有。
And I guess as all of these, sort of, some of them social stories, some of them scientific stories, some of these facts,
所有的这些,有些是社会故事,有些是科学故事,有些是事实,
started to add up, I just thought, like, why are we calling these the sex chromosomes?
层层叠叠加在一起,不禁让我思考,为什么我们要叫它们性染色体?
Or if we are, like, maybe we all like that name, should we just allow ourselves to think about them a little more broadly?
或者说,可能我们就是喜欢这个名字,我们不应该允许自己去思考得更广泛些吗?
Because if we do, like, what insights would we gain, as people, as scientists?
一旦我们这样做了,作为群众,作为科学家,我们能从中学到什么?
And we're at this point where we're thinking about, like, how do we want to teach science,
现在我们在想,我们要怎么教授科学,
what do we want to fund, like, who do we want to be as a society, you know?
我们想要投资什么项目,又或者,我们想塑造一个什么样的社会?
And I just wondered if it wasn't a moment to rethink the biology of X and Y,
于是我在想,也许我们不应该去重新思考XY染色体背后的生物理论,
and at the very least, to remember, like, the footnotes of history,
而是至少要记住历史的注脚,
which is that the dude who came up with the phrase "sex chromosome,"
也就是那个定义了“性染色体”的人,
actually was like, "Hey, everyone, just remember, this is just," and I quote, "a form of shorthand."
实际上想表达的是,“嘿,各位,只要记住,这只是”--我在这里引用了原文--“一种速记法而已。”
We should not take it literally. Thank you.
我们不应该只从字面上理解。谢谢大家。

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