Question

What is DNA fingerprinting? Why is it called fingerprinting?

Answer 1

Hint: In DNA fingerprinting, chemicals are used for isolating DNA strands in order to identify the uniqueness of a person’s genome. The samples are in the form of a sequence of stripes that are further compared with other samples.

Complete answer:
DNA (deoxyribonucleic acid) is like the blueprint of human genetic makeup. A DNA fingerprint, therefore, is a DNA pattern that has a unique sequence that can be distinguished from the DNA patterns of other individuals. It relies on short tandem repeats (STRs). These are unique to individuals. The satellite DNA sections can be compared between the two samples. The Satellite DNA is repetitive DNA that does not code for any specific protein. These non-coding sequences form a major part of the DNA of humans. This helps to study the whole sequence by looking at specific sites for the presence or absence of common markers that can be quickly and easily identified.
Steps of DNA fingerprinting involves:
Isolate the DNA.
     ↓
Digest the DNA with the help of restriction endonuclease enzymes.
     ↓
Separate the digested fragments as per the fragment size by the process of electrophoresis.
     ↓
Blot the separated fragments onto synthetic membranes like nylon.
     ↓
Hybridise the fragments using labelled VNTR probes.
     ↓
Analyse the hybrid fragments.

Note: DNA fingerprinting can also be used to determine how closely species are related to one another. Further, it helps to track their spread over time. This ability to look directly at an organism’s gene markers has made it very easy to understand zoology, botany, agriculture and even human history.