- You might have read

- 你可能已經讀過

that the novel coronavirus is mutating.

該新型冠狀病毒正在發生變異。

That it's changing its genetic sequence as it spreads.

它在傳播過程中改變了它的基因序列。

That's very true.

這是非常正確的。

Scientists have examined the sequences

科學家們已經檢查了這些序列

of hundreds of viruses taken from people around the world,

從世界各地的人身上提取的數百種病毒。

and some are starting to diverge from one another.

而有些則開始相互背離。

The term mutating coronavirus might sound alarming,

變異冠狀病毒這個詞聽起來可能令人震驚。

but it shouldn't be.

但它不應該是這樣。

So far during this pandemic,

到目前為止，在這場大流行中。

mutations have not been a bad thing.

突變並不是一件壞事。

In fact, they've been a bit useful.

事實上，他們已經有點用了。

- And we're gonna try to visualize why that is.

- 我們要試著想象一下這是為什麼。

With an inkjet printer and a Sharpie.

用一臺噴墨打印機和一支夏普筆。

(electronic music)

(電子音樂)

- A virus is essentially a loose strand

- 病毒本質上是一條鬆散的鏈子

of genetic material surrounded by a protein-based wrapper.

遺傳物質被一個基於蛋白質的包裝物所包圍。

Viruses exist to make copies of themselves.

病毒的存在是為了複製自己。

They spread by entering a host

它們通過進入宿主體內傳播

and hijacking its cells to replicate.

並劫持其細胞進行復制。

Mutations are a natural by-product of that process.

突變是這一過程的自然副產品。

The protein that's in charge of making copies

負責製作拷貝的蛋白質

of the virus' genes inside a cell,

病毒的基因在細胞內的作用。

called a polymerase, can make mistakes.

稱為聚合酶，會犯錯誤。

Sometimes it'll slip in an adenine

有時它會滑入一個腺嘌呤

in a spot where there's supposed to be a guanine.

在一個本該有鳥嘌呤的地方。

Other times, multiple different viruses

其他時候，多種不同的病毒

can also end up in the same host body.

也可以在同一個宿主體內結束。

If they both dump their genes into the same cell,

如果他們都把自己的基因傾倒在同一個細胞裡。

some bits and pieces can get swapped around,

一些零碎的東西可以換來換去。

and an entirely new virus is created.

和一個全新的病毒被創造出來。

That process is called recombination.

這一過程被稱為重組。

It was likely some kind of recombination event

這很可能是某種重組事件

that created the new coronavirus.

創造了新的冠狀病毒。

Scientists think that a coronavirus

科學家們認為，一種冠狀病毒

from a bat swapped some genes with another coronavirus,

蝙蝠的一些基因與另一種冠狀病毒進行了交換。

maybe from a different animal.

也許來自不同的動物。

That may have triggered a change in the spike protein

這可能引發了尖峰蛋白的變化

on the virus, the part that binds to cells

病毒上，與細胞結合的部分

and lets the virus hijack them.

並讓病毒劫持它們。

In this case,

在這種情況下。

the protein became good at binding to human cells,

該蛋白質變得善於與人類細胞結合。

so when by chance it found itself in a human eye or nose,

所以當它偶然發現自己在人的眼睛或鼻子裡時。

it could easily latch onto a cell.

它可以很容易地抓到一個細胞。

It started churning out copies of itself

它開始湧現出自己的副本

and jumped to another person, and another,

並跳到另一個人，又跳到另一個人。

until it spread around the globe.

直到它傳遍全球。

Now that the virus is here,

現在病毒來了。

future mutations could change how it acts, in theory.

從理論上講，未來的突變可以改變它的行為方式。

Mutations that create beneficial traits

創造有益性狀的突變

are more likely to stick around,

更有可能堅持下去。

whereas those that could harm the virus tend to fade away.

而那些可能傷害病毒的則往往會逐漸消失。

For a virus, a beneficial mutation might be one

對於一個病毒來說，一個有益的突變可能是一個

that helps it spread by staying airborne longer,

這有助於它通過在空氣中停留更長時間來傳播。

whereas a harmful mutation might be one

而有害的突變可能是一個

that kills its host too quickly,

過快地殺死了它的主人。

limiting its opportunity to spread.

限制了其傳播的機會。

Those kinds of changes could happen with this virus,

這類變化可能發生在這種病毒身上。

but none of them seem to be happening.

但似乎都沒有發生。

A viral genome in New York City might look different

紐約市的病毒基因組可能看起來不同

from one in Washington State,

從華盛頓州的一個。

but the viruses are functionally the same.

但這些病毒在功能上是相同的。

Someone who is infected with a New York virus

感染了紐約病毒的人

probably isn't going to be any better or worse off

可能不會有任何好的或壞的結果

than someone who was infected with a Washington virus.

比感染了華盛頓病毒的人要好。

There are different lineages of the virus,

該病毒有不同的品系。

but there don't seem to be different strains.

但似乎沒有不同的品系。

It's an important distinction.

這是一個重要的區別。

A new strain would have a different biological property,

一個新的菌株會有不同的生物屬性。

like staying airborne longer.

比如在空中停留的時間更長。

A few apparently neutral changes

一些明顯的中性變化

to the genetic code don't meet that bar.

對遺傳密碼的研究並不符合這一標準。

So why haven't new strains appeared?

那麼為什麼沒有出現新的菌種呢？

Well, it's partly because this virus is comfortable.

嗯，部分原因是這種病毒很舒服。

It's already evolved in ways that make it really good

它已經在某些方面進行了演變，使它變得非常好。

at thriving in humans and spreading between them.

在人類中茁壯成長並在他們之間傳播。

So it's not under a lot of evolutionary pressure

所以它沒有受到很多進化的壓力

to get even better at those things.

以便在這些事情上做得更好。

It also has to do with this particular type of virus.

這也與這種特殊類型的病毒有關。

The coronavirus is an RNA virus,

冠狀病毒是一種RNA病毒。

and those usually mutate fast.

而這些通常變異得很快。

Unlike DNA, RNA doesn't have built-in tools

與DNA不同，RNA沒有內置工具

to repair the mistakes made in the copying process.

來修復複製過程中的錯誤。

But coronaviruses like this one

但像這種冠狀病毒

actually do have proofreaders built in.

實際上是有內置的校對器的。

They double-check that they're not making mistakes

他們反覆檢查自己有沒有犯錯

when they copy themselves,

當他們複製自己時。

so they're less likely to slip in the wrong nucleotide.

所以他們不太可能滑入錯誤的核苷酸。

That means today, virus samples

這意味著今天，病毒樣本

from all over the world look pretty similar

世界各地的人看起來都很相似

to the one that first emerged in Wuhan.

到最初在武漢出現的那個。

Many people who have COVID-19 are infected with viruses

許多患有COVID-19的人都感染了病毒

that are less than 10 nucleotides different from any others.

與其他任何核苷酸的差異小於10個核苷酸。

The full genome is around 30,000 nucleotides long,

完整的基因組大約有3萬個核苷酸長。

so those changes are pretty minuscule.

所以這些變化是相當微不足道的。

That's good for vaccines and treatments.

這對疫苗和治療有好處。

It means the virus isn't changing fast enough

這意味著病毒的變化速度不夠快

that drugs and vaccines would stop working.

藥物和疫苗將停止工作。

If a drug works now,

如果一種藥物現在有效。

the specific bit of the virus it targets

它所針對的病毒的特定位

is not likely to change or vanish.

是不可能改變或消失的。

But the pace of mutation, however slow, is useful to us.

但突變的速度，無論多麼緩慢，對我們都是有用的。

It helps scientists track how and where the virus is moving.

它幫助科學家追蹤病毒的移動方式和地點。

If two people have the same mutation,

如果兩個人有相同的突變。

it could mean that their viruses are closely related,

這可能意味著它們的病毒是密切相關的。

and that they're part of a cluster of infections.

而且它們是一個感染群的一部分。

Mutations are how experts

突變是專家們如何

were able to track New York's COVID-19 outbreak

能夠跟蹤紐約的COVID-19疫情。

back to a European lineage.

可以追溯到歐洲的血統。

So mutations happen.

所以發生了突變。

They're part of the natural rhythms of a virus.

它們是病毒的自然節奏的一部分。

They're not inherently good or bad.

它們本身並無好壞之分。

Scientists are watching them closely,

科學家們正在密切關注他們。

but they're not expecting

但他們沒有料到

a science-fictiony monster movie scenario.

一個科幻的怪物電影的場景。

What we see is probably what we're gonna get,

我們看到的可能就是我們要得到的。

at least for a little while.

至少在一小段時間內。

The challenge is understanding it.

挑戰在於理解它。

(electronic music)

(電子音樂)

If you wanna stay up to date

如果你想保持最新的資訊

with all of The Verge's coronavirus coverage,

與The Verge的所有冠狀病毒報道。

head over to theverge.com, thanks for watching,

前往theverge.com，感謝您的觀看。

and don't forget to subscribe.

並不要忘記訂閱。