What is the Difference Between DNA Fingerprinting and DNA Profiling

The key difference between DNA fingerprinting and DNA profiling is that DNA fingerprinting focuses mainly on minisatellites, while DNA profiling mainly focuses on STRs or microsatellites.

DNA fingerprinting and DNA profiling are two molecular biological techniques used to identify individuals based on DNA variation. DNA fingerprinting is used to identify bodies, track down blood relatives, and look for cures for disease while DNA profiling is a method used in both criminal investigations and parentage testing.

CONTENTS

1. Overview and Key Difference
2. What is DNA Fingerprinting 
3. What is DNA Profiling
4. Similarities – DNA Fingerprinting and DNA Profiling
5. DNA Fingerprinting vs. DNA Profiling in Tabular Form
6. FAQ – DNA Fingerprinting and DNA Profiling
7. Summary – DNA Fingerprinting vs. DNA Profiling

What is DNA Fingerprinting?

DNA fingerprinting is a method used to identify an individual from a sample of DNA by looking at unique patterns in the DNA. About 99.9% of the DNA between two humans is the same. The remaining percentage is unique to each human. DNA fingerprinting is mainly based on the variation in minisatellites. Minisatellites are short sequences (10-60 base pairs long) of repetitive DNA that show greater variation among people. The first minisatellite was discovered in 1980.

DNA fingerprinting technique was invented in 1984 by Professor Sir Alec Jeffreys. The process of DNA fingerprinting involves several key steps. First, DNA is extracted, followed by restriction digestion using restriction enzymes. The resulting DNA bands are then separated through gel electrophoresis. Subsequently, the DNA bands are transferred from the delicate gel to a nylon membrane. The nylon membrane is incubated with radioactive probes, and the minisatellites that the probes have attached to are visualized through an X-ray film. Furthermore, DNA fingerprinting is used as evidence in courts to identify bodies, track down blood relatives. and look for cures for diseases.

What is DNA Profiling?

DNA profiling is the process where a specific DNA pattern obtained from a sample of bodily tissue is used to differentiate a person from others. This technique analyses DNA polymorphisms to make a DNA profile that is unique to each person. This method is based on the variation of STRs or microsatellites between people. Unlike DNA fingerprinting, which uses restriction digestion, DNA profiling uses polymerase chain reaction.

The steps in the DNA profiling include DNA extraction, PCR amplification with labelled primers designed to attach to either end of the STR sequence of interest, electrophoresis to separate the fragments according to size, and visualization of the obtained DNA profile through laser. Furthermore, DNA profiling can be used to identify the probable origin of a body fluid sample associated with crime scenes, reveal family history, and identify disaster victims.

What are the Similarities Between DNA Fingerprinting and DNA Profiling?

• DNA fingerprinting and DNA profiling are two molecular biological techniques used to identify individuals based on DNA variation.
• Qualified molecular biologists perform both techniques.
• Both techniques focus on polymorphic regions of the genome.
• Gel electrophoresis is the main step in both techniques.
• Both methods can use biological samples like blood, hair, saliva, semen, etc., for the extraction of DNA.

What is the Difference Between DNA Fingerprinting and DNA Profiling?

DNA fingerprinting relies on the variation of minisatellites from one person to another, while DNA profiling relies on the variation of microsatellites from one person to another. Thus, this is the key difference between DNA fingerprinting and DNA profiling. Furthermore, DNA fingerprinting uses restriction digestion in its procedure, while DNA profiling uses PCR amplification in its procedure.

The infographic below presents the differences between DNA fingerprinting and DNA profiling in tabular form for side-by-side comparison.

FAQ: DNA Fingerprinting and DNA Profiling

What is the difference between DNA fingerprinting and DNA barcoding?

DNA fingerprinting is a technique used to identify individuals based on unique patterns in their DNA, often for forensic or paternity purposes. DNA barcoding, on the other hand, involves identifying and classifying species by analyzing a short, standardized DNA sequence, typically from a specific gene region.

What are the limitations of DNA fingerprinting?

The limitations of DNA fingerprinting include the need for well-preserved and substantial DNA samples, the potential for contamination, and the requirement for specialized equipment and expertise. Additionally, the technique may face challenges in dealing with degraded or mixed DNA samples.

Why are DNA fingerprints unique?

DNA fingerprints are unique due to the individual’s specific DNA sequence, particularly in regions with variable numbers of tandem repeats (VNTRs) or short tandem repeats (STRs). The variations in these repeat patterns create distinct and highly individualized DNA profiles.

Summary – DNA Fingerprinting vs. DNA Profiling

DNA fingerprinting and DNA profiling are two molecular biological techniques used to identify individuals based on DNA variation. DNA fingerprinting is a laboratory technique to determine the probable identity of a person based on variations on minisatellites in DNA sequences. The drawback of this technique was its requirement for large amounts of well-preserved DNA, making it cumbersome. Consequently, the identification of individuals shifted towards using PCR, which is based on short tandem repeats (STRs) or microsatellites, and this method has become standardized, commonly referred to as DNA profiling. This method is mainly a forensic technique that can be used with smaller samples and is well-automated. So, this summarizes the difference between DNA fingerprinting and DNA profiling.

Reference:

1. “DNA Fingerprinting.” Genome.Gov.
2. “DNA Profiling – An Overview.” ScienceDirect Topics.

Image Courtesy:

1. “DNA Fingerprinting (RFLP)” By Retama Libretexts (CC BY-SA 4.0) via Commons Wikimedia
2. “Short Tandem Repeat (STR) analysis” Derivative: Mikael Häggström from the article: Roberta Sitnik, Margareth Afonso Torres, Nydia Strachman Bacal, João Renato Rebello Pinho (2006). Using PCR for molecular monitoring of post-transplantation chimerism. (CC BY 4.0) via Commons Wikimedia