Page 16 - Science Focus (issue 15)

Our ancesto r s have reco rded and DNA cryptography can encode much more
preserved their knowledge and history through
characters and materials like bones and papers.
However, is there a better way to do so in the 21
st
century?
It is true that we can store information in a
printed or a digital version. However, printed
paper will eventually decompose; computers
may break down and the hard drives may fail.
About two decades ago, scientists realized that
“deoxyribonucleic acid” can overcome all these
physical hurdles and properly store information.
Deoxyribonucleic acid, also known as DNA,
is the fundamental molecule for storing genetic
information. DNA is made of four organic bases:
Adenine (A), Guanine (G), Cytosine (C), and
Thymine (T). In nature, these bases are arranged
sequentially to store and provide instructions to our
cells to make proteins, which then control many
functions and features of an organism. Scientists
wondered whether these “genetic characters”
can be utilized to create secret messages in
DNA cryptography, in order to effectively store
information.
An Innovative
Way to Store
Information!
DNA
一種創新的
資料儲存方式！
By Twinkle Poon 潘晴
than simple text. By translating the 1’s and 0’s of
binary code into DNA code, digital data can be
programmed into synthetic DNA, which can then
be decoded back into its original form. Since this
form of information storage allows a large degree
of parallelism , the computing speed for DNA
1
encoded information could reach 1 billion times
per second. Moreover, DNA molecules have a high
storage density: one gram of DNA can encode 215
petabytes (PB; i.e. 215 000 TB) of data.
In 2012, UK scientist Nick Goldman encoded a
total of 739 kilobytes of different file types (ASCII,
PDF, JPEG and MP3) into strands of DNA. The
content encoded includes all 154 Shakespeare
sonnets, the classic 1953 Watson and Crick DNA
structure paper, a color photograph of the
European Bioinformatics Institute, and a 26-second
excerpt from Martin Luther King’s I Have a Dream
speech. Goldman held the record for the amount
of information encoded in DNA until April 2016,
when researchers at Microsoft and the University
of Washington broke the record by capturing a
whopping 200 megabytes (MB) of data with the
help of binary coding. In their ground-breaking feat,
我們的祖先透過文字和不同的物料，例如骨頭或紙
張等，把他們的知識和歷史記錄，並保存下來。但是在 21 世
紀，我們能找到一些更好的方法嗎？
我們的確可以把資料儲存在印刷本或電腦系統，但是，
在二十年前，科學家們意識到「脫氧核糖核酸」可以克服以
紙張終究會分解、電腦可能會失靈、硬碟也可能會故障。大約
上所有的物理障礙並妥善保存資料。
脫氧核糖核酸，也稱為 DNA，是儲存遺傳信息的重要元
素。DNA 由四種鹼基組成：腺嘌呤 (A)，鳥嘌呤 (G)，胞嘧啶
(C) 和胸腺嘧啶 (T)。在自然界中，這些鹼基會連續排列成一
序列，以保存及提供細胞製造蛋白質的指令，從而控制生物
身體上的多種特徵和運作。科學家希望了解這些「基因字元」
是否可以用於 DNA 密碼學，創造出加密 信息，以便有效地儲
存資料。
DNA 加密法又豈止能把簡單文字編碼？通過將 1 和 0
的二進制代碼翻譯成 DNA 密碼，便可以把數據寫入合成
DNA 中，及後可以把其解碼回原來的二進制代碼。這種資
料儲存方式容許很大程度的平行性 ，因此 DNA 訊息的計
1
算速度可以達到每秒 10 億次。此外，DNA 分子具有很高的
儲存密度：1 克 DNA 可以編碼 215 PB（即 215 000 TB）的
資料。