How is "DNA fingerprinting" done?

Question

Eli Ayoub · Accepted Answer

DNA fingerprinting is done by using several techniques, step by step. DNA fingerprinting is not at all a sequencing technique: rather it identifies repetitive sequences present in one's genome. Such repeat sequences also vary in length due to variation in number of repeats, hence called variable number tandem repeats: VNTRs.

DNA fingerprinting is done in many steps: it would involve

collection of biological sample,
extraction of DNA,
amplification of DNA in PCR machine
cutting the DNA in fragments,
arranging the fragments by using electrophoresis,
transferring the fragments on nytrocellulose membrane,
hybridising specific sequences by using radioactive probes,
washing the membrane before developing an X ray film.
The X ray plate will remain as a permanent genetic 'fingerprint' of the person. Such fingerprints are inherited: 50% from mother and 50% from father, hence a person could be easily identified when fingerprints are compared between parents/siblings.

As the processes involved in fingerprinting are expensive, case studies are done in batches and individual results may come after a couuple of months.

Vivian Aronson · Answer

undefined DNA fingerprinting is accomplished through techniques like PCR (polymerase chain reaction) to amplify specific DNA regions, followed by gel electrophoresis to separate fragments based on size, and then analysis using probes or dyes to identify unique patterns.