Among the most popular: paternity and kinship testing , which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption.

最受欢迎的 DNA 测试是父子和系检测，被收养的孩子可以利用它找到自己的亲属，家庭也可以用它追踪到被收养的孩子。

Because...I don't know. It's weird...going your whole life thinking you're related by blood to someone.

因为......我也不知道。感觉很怪，一直以来都以为我和你们是有系的。

Researchers from the University of California have analyzed gene variation in around 2000 people, comparing pairs of unrelated friends with pairs of unrelated strangers.

加利福尼亚大学研究人员分析了2000人左右的基因变异，同时，将没有系的朋友和没有系的陌生人比较。

This way, the surrogate wouldn't be some impersonal incubator. There'd be a family tie.

这样的话，代的就不会是那些毫无亲情的婴了。是有系的。

So imagine their surprise when they discovered they were in fact biological brothers.

所以，你可以想象，他们发现彼此是有系的兄弟时有多惊讶。

It would be just like Greg, and then Greg and I really are more related.

就像格雷格一样，然后我和格雷格才是真的有系的。

He had never thought of it before, taking for granted the tie of their blood.

这一点他以前从未想到过，而是把他们的系当作理所当然的。

Your mother's sacrifice made the bond of blood the strongest shield I could give you.'

你母亲的牺牲使得的纽带成为我能够给你的最强大的保护屏。”

While it's virtually absent in even closely related lowland neighbors.

但那些居住在低地的、甚至与高地居民有密切系的邻居却几乎没有。

Someone that's related to you is your own flesh and blood.

和你有系的人就是你的骨肉亲人。

We don't usually use this to talk about people who aren't related.

我们通常不用这个来描述没有系的人。

If I ask 100 people what the idiom means, most, if not all, will say that it means family relationships are the most important. The blood you share with your relatives represents a strong relationship. We call these family ties.

如果我问100个人这个习语是什么意思，即便不是所有人，大多数人也会说这表明家庭系是最重要的。你和你的亲属共有的系有一种牢固的系。我们称之为家庭纽带。

Even those who weren't related to Perry came to feel a familial bond. He truly was family to me, Spelling says. A protector and a brother.

甚至那些与佩里没有系的人也开始感觉到一种家庭纽带。“他真的是我的家人，”斯佩林说。“一个保护和一个兄弟。”

Now, what I think is the coolest thing about iridescence is how completely distantly related animals can sort of stumble on the same physics for making color.

我认为彩虹色最酷的地方是，在系很远的动物身上会偶然发现相同的产生颜色的物理原理。

Whether the fact that the languages are similar means that the people who speak them are actually distant relatives we don't yet know for sure.

但是不是这些民族只是语言相似或这些民族中的某些是有系的远亲，对此人们不了解任何确切的情况。

In their defense, immigration officials said they would only separate families if the mom was unfit to care for their offspring or if they couldn't prove parentage.

移民官员曾辩护称，只有在母亲不适合照顾孩子或在无法证明系的情况下，他们才会将孩子与家人分离。

The research reopens the question of why these remarkably vocal marine mammals would use their precious resources to feed pups that aren't related to them.

为什么这些声音非常响亮的海洋哺乳动物会使用它们宝贵的资源来喂养与它们没有系的幼崽。

It was then she first mentioned the idea of an annulment on the grounds of consanguinity, that they were too closely related.

正是在那时，她第一次提出了以系为由废除婚姻的想法，因为他们的系太近了。

That, for us, is fascinating, because a whole group of unrelated cats...we just wouldn't necessarily expect that at all.

这在我们看来很神奇，因为对于几只没系的猫猫来说，我们从没想过会出现这种情况。

Well, let's hear from New York City actress and playwright, Sarah Jones, talking about her complicated ethnicity.

我们来听听纽约市女演员兼剧作家萨拉·琼斯讲述她复杂的种族。