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我們都知道 DNA 定序很重要，它可以讓科學家找出疾病的原因、尋求非人為因素肥胖的療法、研發新藥時也可以跳過很多實體實驗的程序，但問題是現有科技只能以花費數小時甚至數天的時間，為短短一小段 DNA 定序，成本偏高。不過一款新開發出的「隨身碟」，只要滴上一滴樣本它就可以幫你定序，比傳統的方法更快、更便宜，大幅改變了基因與遺傳學相關領域的研究方法。
傳統方法耗時費工
面對成百上千個鹼基對組成的基因，過去的定序方法是先找來上千個樣本，把它們搗碎，個別將碎片裡的鹼基對定序，再用軟體做精細的比對，透過碎片間重疊的部份確認排列的先後次序，如此就能重組出原來的順序。這個方法可以確保結果正確無誤，但必須要有足夠的「確認程序」，才不會讓樣本碎片重組的過程中發生接錯的情形，相對來講就是耗時費力。 新的定序法稱做「奈米孔定序法」(Nanopore Sequencing)，可以一次處理長串的 DNA ，也能夠精確定序許多重覆的鹼基對。這款叫做 MinION 的產品，長得就像一個較大的隨身碟，而它的基本配備需求卻很簡單：一台電腦，要有 USB 埠。
運作原理
使用者先滴一滴樣本到 MinION 的晶片上，那裡有許多毛細孔，裡面裝有許多薄膜。接著一種酵素把 DNA 的雙股拆開，並讓其中一股插入只有幾奈米寬的毛孔中。裝置上的電極製造一束離子流，並使它流過毛孔。當鹼基通過毛孔，會阻擋離子、中斷離子流，此時裝置將把離子流被中斷的過程紀錄下來。
接著電腦預先安裝的軟體會開始分析紀錄下來的電子訊號。因為不同鹼基阻擋離子時會形成不同的電子訊號，代表它們將容易被辨識出來。當 DNA 如長長一串繩子慢慢通過毛孔時，上面的鹼基順序就會一一辨識出來。
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