DNA storage Dunhuang murals. Tianjin University provided by
DNA storage technology concept diagram. Photo provided by Tianjin University
Sequence reconstruction algorithm designed based on DeBreying's theory efficiently solves the problems of DNA fracture and degradation. Photo provided by Tianjin University
science fiction blockbuster " Jurassic Park " tells a story: scientists found a piece of amber with prehistoric mosquitoes and obtained the dinosaur genes from the mosquito blood, thus resurrecting the dinosaur that had been extinct for more than 60 million years.
dinosaur biological information is stored in DNA, and it was extracted and restored several years later. This sounds a bit reasonable, but it also makes people breathe.
Recently, a research result of Tianjin University has brought people closer to their imagination. The school's synthetic biology team deposited 10 selected Dunhuang murals into DNA, and through experiments such as accelerated aging, it was found that these mural information can be stored for thousands of years at room temperature and for twenty thousand years at 9.4℃.
"If it is under suitable temperature and other conditions, it is OK to keep it for tens of millions of years." said Yuan Yingjin, Academician of of the Chinese Academy of Sciences and Vice President of Tianjin University.
The small DNA has an amazing storage capacity
The history of the evolution of human civilization and is also a history of the development of information storage technology.
From knotted and recording events, Cangjie’s character creation to modern magneto-optical storage technologies such as tapes and hard disks, data storage helps mankind to continue his thoughts and record brilliant civilization. The invention of papermaking and printing has allowed humans to increase the amount of data they can store by about five orders of magnitude in hundreds of years. In the computer era, data generated by humans has shown explosive growth.
"The whole world is building data centers, and the energy consumption of data centers is amazing." Yuan Yingjin said. People are constantly looking for more massive, more stable and safer storage methods.
The wonderful thing about nature’s magical craftsmanship lies in this - the best memory may be hidden in life.
Since life appeared on Earth, nature has been using DNA to store information, and it has been more than 3 billion years since then. How do human facial features be placed on the face, how do protein in the body synthesize, what color are the eyes... Such complex human genome information are recorded on DNA much smaller than cells and are used from generation to generation.
is different from various artificial storage devices. The DNA is extremely delicate but so durable. It stores the genetic information of countless organisms over the past billions of years, creating the reproduction, evolution and biodiversity .
So, if you "write" a large amount of information onto a small DNA like a USB flash drive or a hard drive, wouldn't it be a big hit in one fell swoop? In fact, when humans discovered the double helix structure of DNA, American and Russian scientists successively proposed the concept of using DNA to store digital information.
Yuanyingjin explained that DNA storage has three most significant advantages over conventional information storage media such as magnetism, optical, and electricity. The biggest advantage is the high storage density. At present, the Tianjin University research team has stored some classic video clips in DNA, and has achieved a volume storage density of 6 orders of magnitude higher than that of ordinary hard disks.
At the same time, the stored information is available for a very long time. This time, researchers stored information of 10 Dunhuang murals in DNA. Combined with innovative algorithms, the DNA molecule can be stored at room temperature for more than a thousand years and at 9.4℃ for 20,000 years. Long-term storage such as
requires very low energy consumption. Yuan Yingjin believes that DNA storage is regarded as a highly promising storage technology and has become a new opportunity to deal with the challenges of data storage growth.
mural "transformation" into DNA requires several steps
DNA information storage principle is divided into two steps - information writing and information reading.
This process actually crosses an extremely difficult gap: it breaks the boundary between organic and inorganic, connecting the two major systems of life and information.
DNA is the abbreviation of DNA , and contains four bases , "A", "T", "C", and "G". If 0, 1, 2, and 3 in the numbers represent one base, it forms a quad-digit storage method, similar to the 0 and 1 binary codes used by the computer.
can realize "dialogue" by encoding conversion. Han Mingzhe, a doctoral student at the Center for Frontier Science of Synthetic Biology at Tianjin University, explained that the digital images of the mural are essentially binary bit strings. "We convert these binary bit strings into quadruple ATGC base sequences through encoding, and then write the base sequences into DNA through DNA synthesis technology, and the data images of the mural are 'changed' into DNA."
Previously, the team successfully synthesized an additional artificial chromosome in Saccharomyces cerevisiae , and stored two pictures and a video information on it, calling it "yeast CD". With the continuous reproduction and expansion of yeast , digital information is also copied inexpensively and stably.
"We pass on the yeast to 100 generations, and we can still perfectly restore the original data." Yuan Yingjin said that if we had a bigger brain and stored the information in a tree, as the tree grew for thousands of years, human descendants can read the information stored thousands of years from this tree at any time from this tree.
This time, the innovation of this young team is that it can realize reliable reading of information under harsh conditions. Han Mingzhe said that the DNA that stores the information of murals is essentially no different from natural DNA. It also has problems such as fracture and degradation caused by long-term storage, which affects the long-term reliability of information storage, which has also become a key scientific issue that needs to be solved urgently.
So, they designed a sequence reconstruction algorithm based on the de Blaine Diagram theory to solve problems such as DNA breakage, which can restore the original information from severely degraded DNA samples.
To verify the long-term reliability of the data, the team prepared a sample of DNA aqueous solution without any special protection, and then accelerated the sample breakage and degradation at a temperature of 70°C for up to ten weeks. Han Mingzhe said: "This process caused more than 80% of DNA fragments to break errors, simulating the degradation of DNA for thousands of years in the natural environment."
Then, the team relied on the designed sequence reconstruction algorithm to accurately assemble and decode more than 96.4% of the fragments, and then solved the problem of missing a small number of fragments through an encoding method, so that the original Dunhuang mural pictures could be restored perfectly.
How far is DNA storage going to be practical?
Although DNA storage is not well known to the public, it is working hard to get out of the laboratory. "It is not far from practical." Yuan Yingjin said that the amazing demand for data storage is the biggest driving force for new technologies to enter the market.
According to international data companies, the total global data volume will reach 175ZB by 2025 (1ZB is ten trillion trillion bytes). By 2024, 30% of digital businesses around the world will conduct DNA storage trials. However, from the current perspective, if DNA storage is to be used on a large scale, especially in China, it still needs to break through several key bottlenecks. The
team analyzed the main challenges facing DNA information storage at present. The high cost of information storage, slow information reading and writing speed, and the inability to efficiently connect to existing information systems are the three main limiting factors.
According to calculations, the current DNA storage write cost is equivalent to the memory storage cost in the 1980s, and to reach the current data storage cost, it still needs to be reduced by 7-8 orders of magnitude.
"The cost of DNA information storage has great potential to decline in the future." Han Mingzhe believes that in the future, we can start from optimizing the synthesis reaction, improving the chip structure, replacing cheap consumables, and optimizing the amount of reagents to significantly reduce the synthesis cost.
At the same time, due to the huge market size in the information storage field, with the application of semiconductor devices and micro-nano processing in the field of DNA information storage, the huge investment in this field will have a significant impact on DNA synthesis technology. The rapid iteration and upgrading of DNA synthesis technology and equipment is also expected to reduce costs quickly. The reading of
DNA information storage depends on sequencing technology, and the reading speed is slower than that of magnetic, optical, electrical and other storage. Currently, the reading speed of of DNA sequencer is still 3-4 orders of magnitude different from that of hard disks - existing electrical and magnetic storage technologies can usually read tens to hundreds of megabytes of data per second. In addition, the standards for DNA storage are still to be established and face the problem of compatibility with existing digital storage systems.
"DNA information storage is an emerging, multidisciplinary deep cross-fusion research direction." Yuan Yingjin believes that DNA storage is very likely to become the main storage medium for huge cold data storage in the future.
The so-called cold data is like the historical data of an archive. It requires the storage of massive information, but it is rarely used in normal times. Because these data require long-term storage and consume a lot of energy, the lifespan of electronic storage devices is often only ten to decades, and requires continuous updates and iterations, which is difficult to meet the needs of cold data storage.
DNA storage still faces many challenges in the practical use. Yuan Yingjin believes that the current breakthrough may be just the tip of the iceberg. "Technical progress requires ten years of patience to sharpen a sword, and a little luck."
China Youth Daily·China Youth Network reporter Hu Chunyan Correspondent Zhao Hui Source: China Youth Daily
Source: China Youth Daily
