CN111737956A - A DNA data storage coding method - Google Patents

Abstract

The invention discloses a DNA data storage coding method, which comprises the steps of firstly converting irrational numbers into binary key character strings, then carrying out logic operation on binary information original texts and binary keys to obtain binary secret text information, and finally converting the binary secret text information into a stored DNA sequence by two bits. The binary key character string conversion method can adopt the method of directly converting decimal irrational numbers into binary numbers and then removing decimal points, or changing odd numbers on each digit position into 1 and even numbers into 0 after removing decimal points from the decimal irrational numbers. The DNA data storage coding method can overcome the defect that more repetitive sequences are easy to generate in the process of generating the DNA sequence and cannot be applied, and has low possibility of being cracked after encryption, thereby exerting the great advantage of DNA digital storage.

Description

A DNA data storage coding method

technical field

The invention discloses a coding method for data storage by using biological genetic information DNA, and belongs to the field of biological technology and information technology.

Background technique

There are various storage carriers for human text, sound, video and other information, such as ancient oracle bones, stone carvings, silk, sheepskin, bamboo slips, and paper; modern records, tapes, floppy disks, CD-ROMs, hard disks, etc. In the 1950s, DNA (deoxyribonucleic acid) was confirmed by scientists as the carrier of biological genetic information. Compared with ordinary information storage carriers, DNA has its own unique natural advantages in data storage: high storage density, 1 gram DNA can preserve all the book content in the world; it is stable and long-term storage, which can reach tens of thousands to millions of years; it is easy to carry, and can be carried by bacteria or living organisms or placed in containers for long-term storage.

DNA is an important carrier of genetic material, a linear or circular double-helix biological macromolecule produced by natural organisms through billions of years of evolution. Its structure is two chain-like complementary bases that back up each other. Traditional information carriers such as paper are mainly represented by graphic characters, etc. Information carriers such as optical discs are represented by binary electrical signals 0/1, while DNA is realized by the sequential arrangement of four bases A/T/G/C. Different sequences Represents different information, equivalent to quaternary.

Generally, in the DNA of organisms, the distribution and ratio of A/T/G/C bases need to be uniform and the repetition of large segments should be minimized. Therefore, the use of DNA as an information carrier has its special requirements. Since the 0 and 1 of the electrical signal and the magnetic signal are realized by whether the electric signal is energized or the direction of the magnetic pole is different, the repeated sequence has no effect on the preservation and replication of information; however, the replication in DNA is carried out through a biological mechanism, and large segments of Repeated sequences, whether it is a single base repeat (such as 100 consecutive A) or a certain length of repeat (such as 100 consecutive ACTT), will lead to errors such as subsequent recombination or mismatch, which seriously affects the preservation of DNA information.

The binary original information can be used to obtain a string of DNA sequences by generating an A/T/G/C base for every two bits, and then the actual DNA of the sequence can be synthesized by chemical synthesis and PCR to store the information. However, since the vast majority of information often has large repetitions. If a certain coding conversion cannot be performed, the generated DNA sequence will have many repeated fragments, which makes it extremely difficult for these DNA sequences to realize the synthesis and replication of DNA molecules biologically. At present, the technology of DNA sequence synthesis and sequence determination has been very mature, and the related costs have been further greatly reduced. Therefore, it is urgent to solve the above application obstacles of DNA data storage and widely promote DNA digital storage methods.

SUMMARY OF THE INVENTION

The technical problem to be solved by the invention

In order to solve the problem that the existing binary original information will generate many repeated sequences during DNA storage, the present invention proposes a DNA data storage encoding method.

Technical solutions

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

A DNA data storage encoding method, comprising the following steps:

Step 1, convert irrational numbers into binary key strings;

Step 2, performing a bitwise logical operation on the original binary information and the binary key string obtained in step 1 to obtain binary ciphertext information;

Step 3: Convert the binary ciphertext information obtained in Step 2 bit by bit, and convert the four combinations of 00, 01, 10, and 11 into four DNA bases of A/T/G/C to form a DNA sequence. .

Further, the conversion method of the binary key string in step 1 is: directly convert the decimal irrational number into binary and then remove the decimal point, or use the decimal irrational number to remove the decimal point and then change the odd number on each digit into 1, and the even number into 1. 0.

Further, the logical operation in step 2 adopts the method of XOR operation or NOT operation.

beneficial effect

Adopting the technical scheme provided by the present invention, compared with the prior art, has the following beneficial effects:

The encoding method of the present invention overcomes the defect that many repetitive sequences are easily generated in the process of DNA sequence generation and thus cannot be applied, and the possibility of being cracked after encryption is small;

The application of the coding method of the present invention will promote the DNA digital storage method and give play to the huge advantages of DNA digital storage.

Description of drawings

Fig. 1 is the flow chart of the data storage method of the present invention;

Fig. 2 is the process example diagram of using the inventive method to store Chinese character "Hua";

FIG. 3 is an example diagram of the process of storing the Chinese character "一" using the method of the present invention.

Detailed ways

In order to further understand the content of the present invention, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

等，方法中的无理数包括但不限于这些无理数本身和由其函数衍生的无理数，如2π/3，

等；As shown in Figure 1, the first step of the method converts irrational numbers into binary key strings, commonly used irrational numbers such as pi, natural base e,

etc., the irrational numbers in the method include but are not limited to these irrational numbers themselves and irrational numbers derived from their functions, such as 2π/3,

Wait;

Taking pi as an example, the first 20 digits converted into binary according to the base conversion rules are: 11.001001000011111101 after removing the decimal point, take the string 11001001000011111101 as the random code key string;

Another way is to change the odd number on each digit of the decimal irrational number to 1, and the even number to 0 to get a random code key string, such as:

Decimal Pi: 3 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2

Corresponding random code key: 1 1 0 1 1 1 0 0 1 1 1 0 1 1 1 1 0

In application, the irrational numbers that generate the binary key string include but are not limited to decimal, and can also be binary itself, quaternary, octal, etc., and only need to complete the binary according to the corresponding conversion rules.

The second step of the method is to perform a bitwise logical operation on the original text of the information and the binary key string. In this embodiment, logical XOR and logical NOT operations are used. The operation rules for logical XOR are: 0^0=0; 0^ 1=1; 1^0=1; 1^1=0; the operation rule of logical negation is: 0|0=1; 0|1=0; 1|0=0; 1|1=1;

In practical applications, since the length of irrational numbers is infinite, such as pi, which can be calculated to trillions of bits at present, the length of the required irrational numbers can be determined according to the length of the actual original binary information. In addition, the random code sequence generated from irrational numbers includes: But it is not limited to starting from the beginning, such as starting from a certain designated position in positive or reverse order, or every other position, every few positions, etc.

In order to simplify the description process, 8-bit binary information is used for illustration here. A specific example is as follows, a represents the original binary information, b represents the random code key binary string, and c represents the binary ciphertext.

Here, four different original information a1, a2, a3, a4 are taken and encoded using the string obtained by taking the parity of the first 8 bits of the pi key:

a1=00000000, a2=11111111, a3=10001110, a4=01010101, b=11011100

(1) The encoding operation is an XOR operation, that is, a^b=c; the reduction operation is an XOR operation, c^b=a.

coding:

a1^b=c1, the bitwise operation result is: 00000000^11011100=11011100

a2^b=c2, the bitwise operation result is: 11111111^11011100=00100011

a3^b=c3, the bitwise operation result is: 10001110^11011100=01010010

a4^b=c4, the bitwise operation result is: 01010101^11011100=10001001

reduction:

c1^b=a1, the bitwise operation result is: 11011100^11011100=00000000

c2^b=a2, the bitwise operation result is: 00100011^11011100=11111111

c3^b=a3, the bitwise operation result is: 01010010^11011100=10001110

c4^b=a4, the bitwise operation result is: 10001001^11011100=01010101

(2) The encoding operation is a non-operation, a|b=c; the reduction operation is a non-operation, c|b=a

coding:

a1|b=c1, the bitwise operation result is: 00000000|11011100=00100011

a2|b=c2, the bitwise operation result is: 11111111|11011100=11011100

a3|b=c3, the bitwise operation result is: 10001110|11011100=10101101

a4|b=c4, the bitwise operation result is: 01010101|11011100=01110110

reduction:

c1|b=a1, the bitwise operation result is: 00100011|11011100=00000000

c2|b=a2, the bitwise operation result is: 11011100|11011100=11111111

c3|b=a3, the bitwise operation result is: 10101101|11011100=10001110

c4|b=a4, the bitwise operation result is: 01110110|11011100=01010101

As can be seen from the above example, the encoded information converts the sequence in the original information, whether all 0s, all 1s, or information with a relatively uniform distribution of 1s and 0s, into information with relatively uniform distribution of 1s and 0s. In practice, the logical operation between the binary key and the original message includes but is not limited to the above two.

The third step of the method is to convert the binary ciphertext information into DNA sequence information bit by bit. 11011100 is converted to DNA sequence to TCTA.

As shown in Figure 2, the Chinese character "Hua" is converted into a 16x16 binary bitmap, and the irrational number π is removed from the decimal point and then takes its 1-256 digits, and the binary number is generated according to the method that the odd number of each digit becomes 1 and the even number becomes 0. The key string is subjected to a bitwise XOR operation with the original binary lattice information, and is converted into a DNA sequence in the manner of 00->A01->C10->G11->T.

As shown in Figure 3, the Chinese character "one" is converted into a 16x16 binary bitmap, and the irrational number π is removed from the decimal point and then takes its 257-512 digits, and the binary number is generated according to the method that the odd number of each digit becomes 1 and the even number becomes 0. The key string is subjected to a bitwise XOR operation with the original binary lattice information, and is converted into a DNA sequence in the manner of 00->A01->C10->G11->T.

The present invention and its embodiments have been described above schematically, and the description is not restrictive, and what is shown in the accompanying drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. Therefore, if those of ordinary skill in the art are inspired by it, without departing from the purpose of the present invention, any structural modes and embodiments similar to this technical solution are designed without creativity, which shall belong to the protection scope of the present invention. .

Claims (5)

1. a DNA data storage coding method, is characterized in that, comprises the following steps: Step S1, convert the irrational number into a binary key string; In step S2, the original binary information and the binary key string obtained in step S1 are subjected to a bitwise logical operation to obtain binary ciphertext information; In step S3, the binary ciphertext information obtained in step S2 is converted bit by bit, and the four combinations of 00, 01, 10, and 11 are converted into four DNA bases of A/T/G/C to form a DNA sequence. . 2. A kind of DNA data storage coding method as claimed in claim 1 is characterized in that, the binary key string conversion method in described step S1 is: after the decimal irrational number is directly converted into binary, the decimal point is removed. 3. a kind of DNA data storage coding method as claimed in claim 1 is characterized in that, the binary key character string conversion method in described step S1 is: after the decimal point irrational number is removed, the odd number on each digit is changed into is 1, and even numbers become 0. 4 . The method for storing and encoding DNA data according to claim 1 , wherein the logical operation in the step S2 is an exclusive OR operation. 5 . 5 . The method for storing and encoding DNA data according to claim 1 , wherein the logical operation in the step S2 is a NOT operation. 6 .

Images