A new method for determining nucleotide sequences in DNA is described. This method uses chain-terminating inhibitors, specifically 2',3'-dideoxy nucleoside triphosphates (ddNTPs) and arabinonucleoside triphosphates (araNTPs), which inhibit DNA polymerase activity. The technique was applied to the DNA of bacteriophage φX174 and is more rapid and accurate than the "plus and minus" method. The principle of the method involves the incorporation of these inhibitors into DNA strands, which prevents further extension of the chain. By using different inhibitors for each nucleotide, the sequence can be determined by analyzing the resulting fragments on a gel. The method uses DNA polymerase, a primer, and a template to synthesize DNA, with the inhibitors terminating the chain at specific positions. The technique was tested on φX174 DNA, and the results showed that sequences could be accurately determined. The method has advantages over previous techniques, including simplicity and accuracy. However, it requires specific inhibitors, which may not be readily available. The method was also compared to other techniques, such as the Maxam-Gilbert method, which uses chemical degradation of DNA. The new method is more suitable for double-stranded DNA and provides more accurate results. The results showed that sequences could be determined with reasonable accuracy, and the method was used to identify the origin of viral strand replication in φX174 DNA. The method was also used to correct errors in the provisional sequence. The method has the potential to be used for sequencing longer DNA fragments and is more efficient than previous methods. The results indicate that the method is a reliable and accurate way to determine DNA sequences.A new method for determining nucleotide sequences in DNA is described. This method uses chain-terminating inhibitors, specifically 2',3'-dideoxy nucleoside triphosphates (ddNTPs) and arabinonucleoside triphosphates (araNTPs), which inhibit DNA polymerase activity. The technique was applied to the DNA of bacteriophage φX174 and is more rapid and accurate than the "plus and minus" method. The principle of the method involves the incorporation of these inhibitors into DNA strands, which prevents further extension of the chain. By using different inhibitors for each nucleotide, the sequence can be determined by analyzing the resulting fragments on a gel. The method uses DNA polymerase, a primer, and a template to synthesize DNA, with the inhibitors terminating the chain at specific positions. The technique was tested on φX174 DNA, and the results showed that sequences could be accurately determined. The method has advantages over previous techniques, including simplicity and accuracy. However, it requires specific inhibitors, which may not be readily available. The method was also compared to other techniques, such as the Maxam-Gilbert method, which uses chemical degradation of DNA. The new method is more suitable for double-stranded DNA and provides more accurate results. The results showed that sequences could be determined with reasonable accuracy, and the method was used to identify the origin of viral strand replication in φX174 DNA. The method was also used to correct errors in the provisional sequence. The method has the potential to be used for sequencing longer DNA fragments and is more efficient than previous methods. The results indicate that the method is a reliable and accurate way to determine DNA sequences.