PCR（Polymerase chain reaction），又稱聚合酶鏈鎖反應，可在體外擴增小片段的DNA，可應用於基因定序、親子關係鑑定、傳染病檢測（如最近的H7N9），甚至在CSI、NCIS等影集也常出現用以確定死者身份或血液來源。
但是文章寫得落落長不如讓我來唱給你聽！
（PCR Song，YouTube影片，作者a1019yuyu）
歌詞：
There was a time when to amplify DNA,
You had to grow tons and tons of tiny cells.
(Oooh) Then along came a guy named Dr. Kary Mullis,
Said you can amplify in vitro just as well.
Just mix your template with a buffer and some primers,
Nucleotides and polymerases too.
Denaturing, annealing, and extending,
Well it’s amazing what heating and cooling and heating will do.
[Chorus]
PCR when you need to detect mutation (detect mutation)
PCR when you need to recombine (recombine)
PCR when you need to find out who the daddy is (who’s your daddy?)
PCR when you need to solve a crime (solve a crime)
歌詞來源：
http://practicality.wordpress.com/2008/01/13/the-pcr-song-with-lyrics/
這首歌生物儀器公司BIO-RAD模仿Michael Jackson於1985年所寫的We are the world，目地當然是要廣告影片最後出現的PCR儀器。但是針對生物學所寫的歌實在太少了！各位同學也可以集思廣益多寫一些朗朗上口又易記的歌曲幫助記憶啦！
原版無字幕版的PCR Song：
http://www.youtube.com/watch?v=x5yPkxCLads
BIO-RAD公司網站：
http://www.bio-rad.com/
