為啥總拿小白鼠做實驗？

While we often refer to "lab rats" and "guinea pigs" as shorthand for test subjects, it's the unassuming mouse that is widely popular in laboratory study. It dominates the labs due to a few factors, among them that they're inexpensive to buy and easy to breed and house.

雖然我們經常認為“實驗大鼠”和“豚鼠”是大部分實驗的對象，但在實驗室研究中最廣泛流行的其實是不起眼的小鼠。小鼠之所以在實驗室這么受歡迎也不是毫無道理，其中最主要的原因便是它們不僅廉價而且很容易繁殖。

But the researchers of the world aren't just choosing mice because they're a cheap date that you can buy in bulk. Consider that the mouse's DNA looks startlingly like ours; in fact, we share more than 90 percent of the same genes as a mouse [source: Koshland Science Museum]. This means that when it comes to the ways our molecules work, you're going to find that mice and people aren't all that different.

但是，科研人員并不僅僅是因為廉價才選擇小鼠作為實驗對象的。令人吃驚的是，小鼠的DNA看起來和我們人類的差不多。事實上，我們人類和小鼠的基因有90%是相同的。這也就意味著，當涉及到分子水平時，你會發(fā)現小鼠和我們人類并沒有那么不同。

Now understand that there are animals that are even closer to us genetically: primates, dogs, pigs. (Yup, you and bacon are practically siblings.) But working with those animals presents more problems. Obviously, they're bigger and more difficult to house and feed. But they also present larger ethical problems that some people are more comfortable dismissing when it comes to our rodent pals. In other words, mice might not be the closest animals to us genetically, but they are one of the closest that we feel comfortable using in studies.

當然了，有些動物在基因上更接近人類，比如靈長類動物、狗以及豬。但是和這些動物一起工作會帶來更多的問題：首先，這些動物的體型都比較大，更加難以飼養(yǎng)。另一方面，使用它們進行實驗也存在更大的倫理問題。而涉及到我們的嚙齒類動物伙伴時，有些人更愿意置之不理。換句話說，小鼠可能不是基因與我們最相近的動物，但在適合用于研究的動物中，小鼠的基因確實更接近人類。

How can studies on mice translate to humans? While we'd like to think that we'd never stoop to running a maze for a treat, the truth is that much of our underlying behavior isn't that different from the behavior of a mouse. There's a reason that tests that measure addiction, reward and learning are conducted on mice: They exhibit the same motivations that we do.

對小鼠的研究為何適用于人類?雖然我們人類決不會屈尊通過走迷宮來獲得治愈，但事實是我們的大部分潛在行為與小鼠的行為并沒有太大的不同。也就是說，在小鼠身上進行一些測試是有原因的：它們常常表現出和我們人類一樣的動機。

The scope of mice-to-human studies is becoming even broader as we learn more about the mouse genome -- and how to manipulate it. Genetically engineered mice might sound like the stuff of horror films, but consider them a scientist's dream. "Knockout" mice are those that have been manipulated so a certain gene is turned off or inactivated; transgenic mice have foreign DNA incorporated into their genome [source: The Jackson Laboratory]. These kind of mice are an extraordinary resource for modeling human disease; for instance, research has found that mice that are genetically mutated to carry the BRCA1 gene (a human breast cancer gene) behave more similarly to human cancer patients than those mice who have had a tumor physically transplanted in. Also, knocking out the leptin gene in mice showed that this hormone regulated appetite. Now, leptin is used in treating some people who are obese .

隨著人類對小鼠基因組的了解越來越多，小鼠對人類的研究也更加重要了?；蚋脑焓舐犉饋硐袷强植离娪袄锏臇|西，但它們其實是一些科學家的夢想。例如，研究發(fā)現，攜帶人類乳腺癌基因的小鼠比那些只是移植了腫瘤細胞的小鼠表現得更像癌癥病人。同時，在小鼠體內“敲除”掉瘦素基因也表明這種激素被用于調節(jié)食欲。現在，瘦素已經被用來治療一些肥胖病人。