强迫症原来都是基因惹的锅

Do you often feel like you want to wash your hands again and again? Or do you ever have the urge to line up the items on your desk? These all may be symptoms of obsessive-compulsive disorder, or OCD, which affects about 2 percent of the world’s population.

你常想一遍又一遍地洗手吗?或者你是否曾有想要把桌上物品整理好冲动?这些或许都是强迫症的症状，全球2%的人口受此影响。

Those who suffer from OCD have difficulty finding successful treatment because doctors don’t clearly understand its causes. But now, a new study has given hope for a future cure.

这些饱受强迫症困扰的人很难得到有效的治疗，因为医生也无法明确病因。而如今，一项新研究带来了未来治愈强迫症的希望。

For the study, which was published in the journal Nature in October, researchers observed humans, dogs and mice. They discovered four genes that may be responsible for obsessive-compulsive behaviors in humans.

在《自然》期刊10月发布的这项研究中，研究人员对人类、狗以及老鼠进行了观察。他们发现四种基因或许是人类强迫症行为的症结所在。

But why observe dogs and mice to learn about humans?

但研究人类为什么还要观察狗和老鼠呢?

“Dogs, it turns out, are surprisingly similar to people,” study author and geneticist Elinor Karlsson, of the Broad Institute of MIT and Harvard University, US, told NPR. “They’re chasing their own tail or chasing shadows like normal, but they’re doing it for hours.”

“事实证明，狗和人类有着惊人的相似性，”该研究作者、来自美国哈佛大学-麻省理工学院布罗德研究所的遗传学家Elinor Karlsson在接受美国全国公共广播电台采访时表示。“有的狗像正常的狗一样追着自己的尾巴或者影子跑，但一跑就是几个小时。”

In the study, researchers made a list of about 600 genes in mice, dogs and humans that they thought might cause OCD, reported NPR. They then compared those genes in two large groups of people – those who don’t have OCD and those who do. In the end, they identified just four genes with mutations in the OCD group. The genes are active in a neurological pathway in the brain, which is believed to help control actions. But the mutations could block the neurological pathway.

据美国全国公共广播电台报道，在研究中，研究人员认为共有600种老鼠、狗以及人类的基因会导致强迫症，并据此制作了一张基因列表。他们将这些基因与两大组人群(有强迫症的人和没有强迫症的人)进行比对。结果发现只有四种基因在患有强迫症的人群中发生了突变。这些被认为有助于控制行为的基因在大脑的神经通路中相当活跃。但突变或许会阻断神经通路。

For example, for people without OCD, when they finish washing their hands, a signal will come, telling them to stop. But for people with OCD, the neurological pathway is blocked, so the message isn’t getting through. As a result, the person will continue to wash their hands.

比如，没有强迫症的人洗完手后会收到一个信号，告诉他们可以停下了。但强迫症患者的神经通路却被阻断了，所以这一信息无法传达。结果就是他们会去不断地洗手。

“OCD and anxiety are kind of like learning disorders,” Marcos Grados, an OCD researcher at Johns Hopkins University School of Medicine, told NPR. “Often with OCD, people have a fear of germs. You can’t touch tables or door knobs and every time it’s the same sensation. You didn’t learn that the last time you touched a door knob, nothing happened. It’s like touching it for the first time ever.”

“强迫症和焦虑症类似于阅读障碍症，”约翰斯·霍普金斯大学医学院的强迫症研究员Marcos Grados在接受美国全国公共广播电台采访时表示。“有强迫症的人往往都会害怕细菌。他们不敢碰桌面或者门把手，每次触碰都会产生同种异样的感觉。他们无法想起上次触碰门把手安然无事的经历，永远都像是第一次的体验。”

However, that doesn’t mean people who have these genetic mutations will always have obsessive-compulsive behaviors, the researchers said. That’s because the disorder also relies on other things, such as one’s environment.

然而，研究人员表示，这并不意味着带有这些基因突变的人就会有强迫症的行为。因为强迫症还受制于环境等其他因素。

According to reports, various existing treatment methods have low success rates in patients. But now that we know where OCD comes from, let’s hope we will soon find an effective way to treat it.

报告表明，现有的各种治疗方式对于强迫症患者都奏效甚微。但如今我们知道了强迫症的症结所在，希望很快就能找到治疗强迫症的有效方法。