Describe DNA fingerprinting: Principle, Procedure, and Applications.

DNA fingerprinting, also known as DNA profiling or genetic fingerprinting, is a technique used to identify and analyze the unique genetic makeup of an individual. It is based on the principle that every individual has a unique DNA sequence, except for identical twins.

The procedure for DNA fingerprinting involves several steps. First, a sample of DNA is collected from the individual, typically through a blood sample, saliva, or hair follicles. The DNA is then extracted and purified from the sample. Next, specific regions of the DNA, known as genetic markers, are amplified using a technique called polymerase chain reaction (PCR). These markers are highly variable among individuals and are used to create a unique DNA profile for each person.

The amplified DNA fragments are then separated and analyzed using a technique called gel electrophoresis. This process separates the DNA fragments based on their size, allowing for the comparison of DNA profiles between different individuals. The resulting DNA profile is a unique pattern of bands that can be used to identify and distinguish individuals.

DNA fingerprinting has a wide range of applications in various fields, including forensic science, paternity testing, and genetic research. In forensic science, DNA fingerprinting is used to identify suspects, link individuals to crime scenes, and exonerate wrongly accused individuals. In paternity testing, DNA fingerprinting is used to determine biological relationships between individuals. In genetic research, DNA fingerprinting is used to study genetic variations, track the spread of diseases, and identify genetic disorders.

Overall, DNA fingerprinting is a powerful tool for identifying individuals and studying genetic diversity, with a wide range of applications in various fields.

DNA Fingerprinting

Principle:

DNA fingerprinting, also known as genetic fingerprinting, is a technique used to identify a specific individual based on their unique DNA profile. It exploits the principle that each person's DNA is unique, except for identical twins.

Procedure:

1. Sample Collection:
- A sample of DNA is obtained from an individual, such as from their saliva, blood, or hair.

2. DNA Extraction:
- The DNA is extracted from the cells using specific chemicals and protocols.

3. DNA Amplification (PCR):
- Polymerase Chain Reaction (PCR) is used to make multiple copies of specific DNA regions called Variable Number Tandem Repeats (VNTRs). VNTRs are short DNA sequences that repeat a variable number of times between individuals.

4. Gel Electrophoresis:
- The amplified DNA is separated according to size using gel electrophoresis. The different sizes of repeated VNTRs will produce distinct bands on the gel.

5. Band Analysis:
- The pattern of bands on the gel is analyzed to determine the individual's unique DNA profile.

Applications:

Forensic Science:

- Identifying criminal suspects
- Establishing paternity or other biological relationships
- Solving missing persons cases

Medical Applications:

- Genetic disease diagnosis and prediction
- Identifying organ donors and recipients
- Personalized medicine

Research:

- Studying genetic variation in populations
- Understanding the evolution of species
- Identifying individuals in ecological studies

Other Applications:

- Immigration and citizenship identification
- Establishing insurance claims
- Archaeological DNA analysis

Advantages of DNA Fingerprinting:

- High accuracy and specificity
- Applicable to very small amounts of DNA
- Can be used on a wide range of biological samples
- Can differentiate between identical twins