The function of the dideoxy (dd) nucleotides that are used in the Sanger method of DNA sequencing is to

Question

Quizplus · Accepted Answer

The dideoxy (dd) nucleotides lack a 3'OH group and therefore terminate DNA synthesis when incorporated into the growing strand by DNA polymerase. In the Sanger method, a mixture of regular deoxynucleotides (dNTPs) and small amounts of fluorescently labeled ddNTPs (each labeled with a different color) are added to a DNA template. As the DNA polymerase elongates the new strand, a random ddNTP is occasionally incorporated, which stops further elongation. The resulting mixture of DNA fragments of different lengths with a fluorescent tag at their 3' end can then be separated by size using gel electrophoresis and detected by fluorescence. This method allows for the determination of the sequence of the template DNA strand.

The Function of the Dideoxy (Dd) Nucleotides That Are Used