“When I get a little money I buy books; if any is left I buy food and clothes.”
I love books. As soon as you walk into our house, you will see that this is true. Bookcases line practically every wall, each one jam-packed with books. Then there are the stacks of books that don’t fit on the bookshelves…
Credit: Fazale Rana
For people who love books, storage (and ready accessibility) is a problem. Without a doubt, this explains the popularity of the Kindle and the Nook. (I have yet to purchase one because I prefer the feel of an actual book in my hands. But soon I may have no choice, if for no other reason than for lack of space for more bookcases in our house.)
This accomplishment only scratches the surface of possibilities that await the use of DNA as a storage medium. One gram of DNA can hold up to 455 exabytes (one exabyte equals 1018 bytes). In comparison, a CD-ROM holds about 700 million (7 x 108) bytes of data. (One gram of DNA holds the equivalent amount of data as 600 billion CD-ROMs. Assuming a typical book requires 1 megabyte of data-storage capacity, then one gram of DNA could harbor 455 trillion books.)
In spite of the researchers' success, it currently isn’t practical or cost-effective to use DNA to store data (or to house the Library of Congress). But change is coming. The use of inorganic data-storage based systems, like CD-ROMs, will soon be an antiquated technology. And organic materials, like DNA, may become the storage medium of choice.
While the technological uses for DNA storage have yet to materialize, the full impact of this type of work is felt in the creation/evolution controversy. The research by the team from Harvard and John Hopkins (and others) helps to powerfully advance the case for a Creator.
DNA and the Case for the Creator
As I discussed in The Cell’s Design—and elsewhere—one of the most provocative arguments for intelligent design centers on the recognition that DNA (and other biomolecules) is an information-based system. Common, everyday experience teaches that information derives solely from the activity of human beings. So, by analogy, the biochemical information systems, too, should come from a divine Mind. The stark similarity between the way that biochemical information systems are structured and the structure of information systems designed by humans deepens the analogy (for an example, go here).
Yet skeptics argue that biochemical information is not genuine information. Instead, they maintain that when scientists refer to DNA as an information storage molecule they are making use of an illustrative analogy—a scientific metaphor—and nothing more. They accuse creationists and intelligent design proponents of misconstruing their use of analogical language to make the case for design.2
But the work by the Harvard and Johns Hopkins scientists questions the validity of this objection.
DNA Data Storage
These researchers are not the first scientists to store information within the nucleotide sequences of DNA. However, they are to be credited for storing the most information to-date, and, in doing so, addressing some limitations of this technology.
In order to encode specific information into the nucleotide sequence of DNA, researchers must make DNA molecules with a prescribed sequence without error. Yet, with the current synthesis technology, the number of errors in the DNA sequence increases with the length of the sequence. In other words, researchers can make “perfect” sequences, but only if they are relatively short—not long enough to store any appreciable amount of data.
Stabilizing the encoded DNA molecules poses another challenge. DNA tends to become damaged or broken down over time. When this happens, information is lost.
To sidestep the first of these two issues, the researchers encoded the book’s contents into small DNA fragments—devoting roughly two-thirds of the sequence for data and the remainder for information that can be used to locate the content within the entire data block. In a sense, this approach is analogous to using page numbers to order and locate the contents of a book. By making short DNA sequences, the researchers were able to ensure that few, if any, errors were introduced into the sequences of the synthesized DNA fragments.
The researchers addressed the problem of stabilizing the synthesized DNA by making multiple copies of each fragment. In this way, if one of the fragments becomes damaged or breaks down, the redundancy prevents the information from being lost completely.
As impressive as this advance is, the practical implementation of DNA storage is still a dream for the future. The chief hang-up at this point is the time and cost to synthesize the amount of DNA required to store a book, and then, in turn, to read out the information. But these efficiency concerns may not hinder progress for long, as the cost of making and sequencing DNA plummets.
DNA Data Storage and the Case for Design
Even if the work on DNA storage never translates into practical applications, it still has profound implications for the creation/evolution controversy. These scientists were able to store information in DNA, because DNA is an information-storage system. In other words, it is hard for skeptics to argue that biochemical information is only a metaphor, when biotechnologists are using DNA to store an entire book’s worth of information.
The more that DNA becomes the focal point of new biotechnology application, the more the claim that life comes from the outworking of undirected evolutionary process becomes the same old tired story. It is time to “turn some pages.”