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In the 1950s, a group of ranchers in Idaho were baffled when their sheep gave birth to lambs with a singular deformity.
在20世纪50年代，爱达荷州的一群牧场工人对新生的畸形小羊而困惑不已。
Mystified by these cyclops sheep, they called in scientists from the U.S. Department of Agriculture to investigate.
因为对这些独眼羊感到困惑，他们从美国农业部找来科学家进行调查。
The researchers hypothesized that the pregnant ewes had snacked on poisonous birth defect-causing plants.
研究者提出假说，认为怀孕的母羊吃下了有毒的、会引起出生缺陷的植物。
They collected the local flora and fed samples to lab rats, but struggled to replicate the effect.
他们采集了当地的植物群，并将样本喂给实验老鼠，但是难以达到相同的效果。
So they decided to directly observe the sheep with one scientist even living with the herd for three summers.
因此他们决定直接观察羊群，一位科学家甚至与羊群一起住了三个夏天。
After a decade of trial and error, the scientists finally found the culprit, wild corn lilies.
经过十年的试验和错误之后，科学家终于找到了使羊群畸形的病因：野生玉米百合。
The lilies contained an active molecule with six connected rings that they named cyclopamine in reference to the cyclops sheep.
百合含有一个带六个连接环的活性分子，这被称为环杷明，以独眼畸形羊命名。
They didn't know exactly how cyclopamine caused the defect but told ranchers to steer clear.
他们并不清楚环杷明是如何导致缺陷的，但告诉牧场工人让羊群避开这种植物。
It took about four decades before a team of biologists, led by Professor Philip Beachy, stumbled upon the answer.
一个由菲利普·比奇领导的生物学家团队花了大约四十年蹒跚前行寻找答案。
His lab was studying a specific gene found in many species, from mice to humans, called the hedgehog gene.
他的实验室正在研究一个从许多物种中都发现的一个特定的基因，从老鼠到人类身上都有，叫做hedgehog gene（刺猬蛋白基因）。
It was named by two scientists, who later shared the Noble Prize for their work,
两位科学家命名了这一基因，他们随后获得诺贝尔奖，
who found that mutating this gene in fruit flies produced pointy spikes like a hedgehog.
他们发现，果蝇体内这一变异的基因会产生像刺猬一样的尖刺。
Beachy and his colleagues performed genetic modifications to turn off the hedgehog genes in mice.
比奇和他的同事通过遗传修饰来关闭老鼠体内的刺猬基因。
This resulted in severe defects in the development of their brains, organs, and eyes or, rather, eye.
这会导致大脑、器官、眼睛发展的严重缺陷，更确切的说，一只眼睛。
Then while perusing a textbook, Beachy came across photos of the cyclops sheep and realized what had eluded scientists for four decades.
在研读一本教科书时，比奇发现了独眼羊的照片，意识到了迷惑科学家们长达四十年的问题。
Something must have gone awry involving the hedgehog gene. Let's take a step back.
一些涉及刺猬蛋白基因的东西一定是出错了。让我们退一步看看。
Genes contain instructions that tell cells what to do and when to do it, and they communicate their directives using proteins.
基因会告诉细胞做什么和什么时候做的指令，它们运用蛋白质来交流这些指令。
The hedgehog gene itself tells cells to release a so-called hedgehog protein, which kicks off a complex series of cellular signals.
刺猬蛋白基因自身会告诉细胞释放一种所谓的刺猬蛋白，它会开启一系列复杂的细胞信号。
Here's how it works in normal healthy development. Hedgehog protein latches on to a protein called patched.
在正常的健康发展状态下，它是这样工作的。刺猬蛋白锁定在一种叫补丁的蛋白质上。
That inhibits, or holds, patched back, allowing another protein called smoothened to freely signal the cells,
那会抑制，或者阻止补丁，让另一种叫smoothened的蛋白来自由标记细胞，
telling them where to go and what kind of tissues to become.
告诉细胞要去往那里，要成为哪一种组织。
Cyclopamine, say in the form of a delicious corn lily, interrupts this pathway by binding onto smoothened.
以美味的玉米百合的形式而言，环杷明通过和smoothened的绑定，来阻断通路。
That locks smoothened up so that it's unable to send the signals needed
它锁住了smoothened，因此让其无法传递信号
to mold the brain into two hemispheres, and form fingers or separate eyes.
让大脑形成两个半球并形成手指和分开的眼睛。
So even though the hedgehog protein is still doing its job of keeping the way clear for smoothened,
因此，虽然刺猬蛋白仍在工作，帮助smoothened保持通路顺畅，
cyclopamine blocks smoothened from passing along its chemical message.
但环杷明阻挡了smoothened通过化学信息传递。
That settled the science behind the one-eyed sheep, but Beachy and his team caught the glimmer of another more beneficial connection.
这就解答了独眼羊背后的科学问题，但是比奇和他的团队从另一个更有益的联系中找到了一线微光。
They noted that uncontrolled activation of the smoothened protein was associated with a human syndrome.
他们指出，smoothened蛋白质不受控制的激活和一种人类综合症相关。
It's known as Basal Cell Nevus Syndrome, and it predisposes people to certain cancers.
它被称作基底细胞痣综合征，并且它使人们易于患特定的癌症。
The scientists proposed putting cyclopamine's smoothened binding powers to good use as a treatment for these cancers,
科学家提出将环杷明smoothened的捆绑功能运用到治疗这些癌症上，
as long as the patient wasn't pregnant.
只要病人没有怀孕的话。
Unfortunately, researchers eventually found that cyclopamine causes negative side effects,
不幸的是，研究者最终发现，环杷明会导致负面的副作用，
and its chemical properties make it difficult to work with.
并且它的化学性质让人们难以把握。
But they did discover that closely related molecules are safe and effective,
但他们确实发现了与之密切相关的分子是安全有效的，
and two of these drugs were approved in 2012 and 2015 as skin cancer medicines.
并且其中两种在2012年和2015年的时候被批准为皮肤癌药物。
When those farmers first saw the cyclops sheep, they could have chalked it up to a freak genetic mutation and walked away.
当那些农民第一次见到独眼羊的时候，他们本可以将其记作怪异的基因突变产物并走开。
Instead, their decision to investigate turned a mystery into medicine showing that sometimes there's more than meets the eye.
但相反的是，他们做出调查的决定将这一谜团转变为药物，这表明了有时候有些事实是眼睛看不到的。
