What is the shotgun method in genetics?

The shotgun method is used to sequence of long chains of deoxyribonucleic acid (DNA). It relies on another method of DNA sequencing called Termination method. With the shotgun method, scientists of the sequential part of the DNA chain and the results create a continuous sequence.

sequencing is the process of finding the atomic composition of the molecule and the investigation of the chemical bonds that combine these atoms. In DNA, sequencing is used to find the order in which certain molecules occur. These molecules are called nucleotides. Four nucleotide bases are adenin, guanine, cytosine and thymin.

One way of sequencing long DNA strands is the use of a shotgun method. In this method, DNA is divided into random fragments. The resulting segments are then sequenched using the method called the Termination method. Termination of the string is the choice method for short DNA sequences. It uses several harsh chemicals and lower amounts of radioactivity than the short sequence methods.

in the termination methodThe Etězce is divided into four sequence reactions. Each contains all four nucleotides and enzyme, which acts as a catalyst called DNA polymerase. To each sequential reaction is then added dideoxynuleotide, which is essentially a nucleotide missing part of its sugar sequence. After processing these reactions, scientists are able to display them and read the DNA sequence.

During the DNA sequencing shotgun method, all this happens several times using different random DNA fragments. This results in more overlapping parts of the sequential DNA. The computer program then uses the overlapping section to create a continuous DNA sequence.

The problem with the shotgun method is that DNA is incredibly complex. Often it contains recurring sequences that look the same but come from different parts of TDNA. The complete set of human DNA, called the human genome, has more than three billion couples of bases.The only way to make sure that the location of repeated sequences is correct is to perform more random values, so each part is sequenced several times. Yet there are errors.

The shotgun sequence method was the tip of the DNA sequencing until 2005. Since then, scientists have created a new generation sequencing that works much faster. The accuracy of the individual values ​​is less than when the shotgun sequence, but scientists are compensated by the fact that they are able to make more reading in a shorter time.