Final answer:
The dideoxy chain termination method, or Sanger sequencing, uses fluorescently labeled ddNTPs to terminate DNA replication at specific nucleotides, producing fragments that are separated by capillary electrophoresis and read from an electropherogram.
Step-by-step explanation:
The dideoxy chain termination method, also known as the Sanger sequencing, is a technique for determining the nucleotide sequence of DNA. Frederick Sanger developed this method, which uses dideoxynucleotides (ddNTPs) to terminate DNA synthesis at specific points, thereby creating DNA fragments of varying lengths. These ddNTPs differ from regular deoxynucleotides (dNTPs) as they lack a 3' hydroxyl group (-OH) on the sugar backbone, preventing further extension of the DNA strand. This process results in numerous DNA fragments that terminate at each of the four nucleotides, which are then separated by size via capillary electrophoresis. Each ddNTP is fluorescently labeled with a different color, which allows the sequence to be read from the resulting electropherogram produced by a laser scanner.