Question

Schematic representation of DNA fingerprints are shown below:
(Hints: C is a sample taken from a crime scene, A and B from two suspected individual)
a) Which one of the suspected individuals may be involved in the crime?
b) Write any other use of DNA fingerprinting.

Answer 1

Hint: DNA fingerprinting is a technique that uses unique patterns in a person's DNA to identify them from a sample of DNA. In criminal investigations, DNA fingerprinting is a laboratory approach for establishing a relationship between biological evidence and a suspect. A DNA sample from a crime scene and a DNA sample from a suspect are compared. If the two DNA profiles match, the evidence was obtained from that individual. If the two DNA profiles do not match, the evidence cannot have originated with the suspect. Paternity can also be established through DNA fingerprinting.
Complete answer:
Individual B may have been engaged in the crime since his DNA matches a DNA segment found at the site.
Genes are short DNA strand sequences that are responsible for an individual's distinct features. PCR is a technique for amplifying the DNA molecules in a tiny sample so that a large amount of DNA sequence can be obtained for the test. The restriction fragment length polymorphism comes next (RFLP). By recognising a specific sequence pattern to the Variable Number Tandem Repeats, RFLP analysis is utilised to identify the repeated sequences, which forms that individual's DNA profile. DNA fingerprinting is based on this principle.
DNA fingerprinting is also employed in paternity and maternity cases, as well as in the detection of hereditary illnesses.

Note:
The following are the steps involved in DNA fingerprinting:
Isolating the DNA is the first step.
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Restriction endonuclease enzymes are used to break down DNA.
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Electrophoresis is used to separate the digested particles according to their size.
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Blotting the fragmented fragments onto nylon-based synthetic membranes.
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Using tagged VNTR probes, hybridise the fragments
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Autoradiography was used to examine the hybrid pieces.

Applications of DNA fingerprinting: It's also used to figure out how common a certain gene is in a population, which leads to diversity. Fingerprinting can be used to trace the role of a change in gene frequency or genetic drift in the evolution of a species.