Today DNA Fingerprinting is a necessary tool for varied purposes which uses the DNA uniqueness due to DNA Polymorphism.

What is DNA Fingerprinting?

• DNA fingerprinting is a scientific technique used to identify individuals based on their unique genetic profiles.
• DNA fingerprinting is a process of identifying individuals based on specific DNA sequences called short tandem repeats (STRs).
• It is used for establishing genetic relationships, criminal investigations, and forensic identification.
• DNA fingerprints can be obtained from various biological samples such as blood, saliva, sweat, semen, skin cells, bones, and teeth.
• DNA fingerprinting is highly reliable, as every person (except identical twins) has a unique DNA profile.
  

About DNA Polymorphism

• DNA polymorphisms are small variations in DNA sequences that differentiate individuals.
• These variations occur due to differences in inherited DNA from both parents.
• They are essential for tracing ancestry, identifying individuals, and understanding genetic diversity.

Molecular Basis of DNA Polymorphism

• Arises from mutations like SNPs (Single Nucleotide Polymorphisms) and VNTRs (Variable Number Tandem Repeats).
• Involves genetic variations in non-coding and coding regions of DNA.
• Affects gene expression, protein function, and phenotype variability.
• Can result from genetic recombination, replication errors, or environmental factors.

Evolutionary Significance of Polymorphic DNA Sequences

• Enhances genetic diversity, enabling species to adapt to changing environments.
• Plays a crucial role in natural selection and evolutionary fitness.
• Helps trace ancestry and evolutionary relationships among populations.
• Aids in understanding disease susceptibility and resistance in different genetic groups.

About Short Tandem Repeats (STRs)

• STRs are repetitive DNA sequences that vary in length between individuals.
• Each STR consists of short repeating units of DNA bases (A, T, G, C).
• These variations in repeat numbers at specific locations form the basis of DNA fingerprinting.
• STR analysis is commonly used in criminal investigations and genetic identification.

DNA Copying (PCR Process) Vs DNA Fingerprinting

Applications of DNA Fingerprinting

• Forensic Science: Identifies criminals using DNA evidence from crime scenes.
• Paternity Testing: Establishes biological relationships.
• Disaster Victim Identification: Helps identify mortal remains.
• Medical Applications: Assists in organ transplantation compatibility.
• Exoneration of Wrongly Accused Individuals: Used in retrials and cold case investigations.

Ethical and Legal Issues in DNA Polymorphism Studies

• Raises concerns about genetic privacy and potential misuse of genetic data.
• Issues of informed consent and ownership of genetic information.
• Potential for genetic discrimination in insurance and employment.
• Legal challenges in forensic applications and ancestry testing.