But for the remaining .1%, one person might have an adenine where another person has a guanine.

但对于剩下的0.1%，一个人可能有另一个人有鸟。

It was known that DNA had four chemical components - called adenine, guanine, cytosine, and thiamine - and that these paired up in particular ways.

当时已经知道，DNA含有4种化学成分——、鸟、胞嘧啶和胸嘧啶——这4种成分总是以特殊的配对列。

The bases - the letters of the genetic alphabet - consist of the four nucleotides mentioned a page or two back: adenine, thiamine, guanine, and cytosine.

碱基——基因子母表中的字母——由前面我们提到的、鸟、胞嘧吟和胸嘧啶4种核苷酸组成。

Nucleotides of DNA are made out of a sugar deoxyribose, a phosphate, and one of the four nuclear bases: adenine, cytosine, guanine, and thymine or A, C, G, T for short.

DNA的核苷酸由脱氧核糖、磷酸以及四个核碱基之一组成，分别是、胞嘧啶、鸟与胸嘧啶，或简称A、C、G、T。

Nucleotides of DNA are made up of a sugar - deoxyribose, a phosphate, and one of the four nucleobases - adenine, cytosine, guanine, and thymine - or A, C, G, T for short.

DNA的核苷酸由一分子单糖-脱氧核糖、一分子磷酸与四种核碱基之一的（A）、胞嘧啶（C）、鸟（G）或胸嘧啶（T）组成。