cr.什么是CNA和CNV？

When I search for what is CNV, the term CNA also pops up in every article which makes me confused because I am not from a biology background. So far my understanding is, both CNV and CNA are duplication, insertion, deletion of base pairs. For example, if GCGATGA appears more than once in a DNA, then it is either CNV or CNA. I also know that the copy number must be >1kb. After reading some articles I got this general idea about the terms but not sure if I am correct though. It would be nice if someone explains both terms.

提问：每篇文章中都会出现CNA一词，这使我感到困惑，因为我不是生物学背景的人。 到目前为止，我的理解是，CNV和CNA都是重复，插入，删除碱基对。 例如，如果GCGATGA在一个DNA中出现多次，则它是CNV或CNA。 我也知道拷贝数必须大于1kb。 阅读一些文章后，我对这些术语有了大致了解，但是不确定我是否正确。

回答：

Typically, CNV refers to germline events, which are variants in the population. CNA usually refers to somatic events, like those found in tumors. They are sometimes used interchangeably.

Confusingly, this is different from single-nucleotide events, which are SNPs (germline events in the population) and SNVs (somatic events).

No one said the nomenclature had to make sense! (I mean, have you seen how we name genes?!)

One more comment - the example you give, of GCGATGA appearing more than once, is usually referred to as an indel. Generally speaking, SV/CNVs are bigger than 1kb, indels are smaller than 100bp, and there's also a weird middle range where the terms are often mixed.

通常，CNV指种系事件，是种群中的变体。 CNA通常指的是体细胞事件，就像在肿瘤中发现的那样。 它们有时可以互换使用。

令人困惑的是，这不同于单核苷酸事件，即SNP（群体中的种系事件）和SNV（体细胞事件）。

没有人说这个命名法必须合理！ （我的意思是，您是否知道我们如何命名基因？！）

另外一个评论-您给出的关于GCGATGA的示例多次出现，通常被称为indel。 一般而言，SV / CNV大于1kb，插入缺失小于100bp，并且还有一个奇怪的中间范围，其中经常混用术语。

提问：

Well, then why CNV is more studied than CNA? If we look in the TCGA database, each cancer cases have files for CNV but nothing for CNA. If CNA is found in tumor cells, shouldn't we study CNA instead of CNV?

那么，为什么CNV比CNA研究的更多？ 如果我们在TCGA数据库中查找，每个癌症病例都有CNV文件，但没有CNA文件。 如果在肿瘤细胞中发现CNA，我们是否应该研究CNA而不是CNV？

回答：

As Chris mentioned:

They are sometimes used interchangeably.

TCGA is looking at the somatic copy number differences.

Yes, this is correct. In TCGA, for whatever reason, the nomenclature used was CNV. They're used interchangeably enough that you're pretty much always going to have to look at the context to figure out which one is being discussed.

正如克里斯所说：它们有时可以互换使用。TCGA正在研究体CN差异。

是的，这是正确的。 在TCGA中，无论出于何种原因，使用的术语都是CNV。 它们已经足够互换使用，因此您几乎总是不得不查看上下文以确定正在讨论的内容。

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