Dideoxy method

Definition

The dideoxy method, also known as Sanger sequencing, is a DNA sequencing technique that uses chain-terminating nucleotides to determine the nucleotide sequence of DNA. It was developed by Frederick Sanger in 1977.

5 Must Know Facts For Your Next Test

1. The dideoxy method relies on the incorporation of dideoxynucleotides (ddNTPs) which terminate DNA strand elongation.
2. Each of the four ddNTPs is labeled with a distinct fluorescent dye for easy identification during analysis.
3. DNA polymerase enzyme is essential for adding nucleotides to the growing DNA strand during this method.
4. Capillary electrophoresis is commonly used to separate and detect the fragments generated by Sanger sequencing.
5. Sanger sequencing is considered the gold standard for accuracy in DNA sequencing.

Review Questions

• What role do dideoxynucleotides (ddNTPs) play in the dideoxy method?
• Why is fluorescence labeling important in Sanger sequencing?
• How are DNA fragments separated and analyzed in this method?

Related terms

DNA Polymerase: An enzyme that synthesizes new strands of DNA complementary to the template strand.

Capillary Electrophoresis: A technique used to separate molecules based on their size and charge using an electric field.

Fluorescent Dye Labeling: A method where fluorescent dyes are attached to molecules allowing their detection and analysis.