DNA fingerprinting is a technique used to recognize the features of DNA of a details individual well-known as DNA profile. The DNA profile is unique to a details individual. The is generated based on the brief tandem repeats (STRs), species of repeating facets in the satellite DNA. Together the DNA profile of a particular individual is unique, it have the right to be used to recognize individuals. Therefore, DNA fingerprinting is offered in paternity testing and also forensic investigations. In forensic testing, the amplifying power of PCR theatre a critical role in recovering information from very tiny or degraded samples.

You are watching: Why did the invention of pcr make dna fingerprinting possible

Key areas Covered

1. What is DNA Fingerprinting – Definition, Procedure, Role 2. Why did the development of PCR do DNA Fingerprinting Possible – usage of PCR in DNA Fingerprinting

Key Terms: DNA Fingerprinting, DNA Profile, Forensic Investigations, Paternity Testing, PCR, brief Tandem Repeats (STRs) 


What is DNA Fingerprinting

DNA fingerprinting is a method used in the to know of individuals based on the distinct patterns of your DNA. This method was arisen by teacher Alec Jeffreys in 1984. The patterns of the repeating elements called brief tandem repeats (STRs) are subjected to the analysis. The STRs belong to the non-coding areas of the genome found in the centromeric regions. They are a kind of satellite DNA. Shorts order of nucleotides (2-6 base pairs) are recurring a variable number of times in STRs. Because individuals have actually a different number of repeats in ~ a provided locus, the DNA profile is distinctive to a details individual. The process of DNA fingerprinting is displayed in figure 1.


Figure 1: DNA Fingerprinting

DNA Fingerprinting Procedure

A DNA sample is isolated indigenous a organic sample (blood, saliva, semen).

Application that DNA Fingerprinting

DNA fingerprinting is used in both paternity testing and forensic investigations.

Paternity Testing

Since a kid inherits fifty percent of the chromosomes from each parent, he has actually a combination of parental fads of STRs. A paternity trial and error diagram is displayed in figure 2.


Figure 2: Paternity Testing

When mother’s mrs bands room subtracted indigenous the child’s DNA profile, the remaining bands belong to #1 person. Therefore, he must be the biological father that the child.

Forensic Studies

DNA fingerprinting is additionally used in the forensic research studies to identify the suspect by compare the DNA profiles. However, the biological sample might be very small or degraded together it needs to be collected from a crime scene.

Why go the development of PCR make DNA Fingerprinting Possible

The organic samples gathered from a crime scene have the right to either it is in very little or degraded. Therefore, the amount of satellite DNA may not be sufficient for detection in a gel. PCR is supplied to amplify the STR regions of the genome in stimulate to attain a considerable variety of DNA because that the restriction digestion. Hence, the use of PCR in DNA fingerprinting rises the discriminating strength of the process.


DNA fingerprinting is the process of identify the DNA file of one individual. The STRs are used to obtain the banding pattern well-known as DNA profile. The DNA profile is distinct per individuals and therefore, it have the right to be supplied in the to know of people in both paternity testing and also forensic studies. However, little or degraded samples may produce bad discrimination in between samples. Therefore, PCR can be supplied to amplify the STR regions to acquire high-intense banding trends on a gel.

See more: A Guide On How Much Propane Does A Tankless Water Heater Use ?


1. Roewer, Lutz. “DNA Fingerprinting in Forensics: Past, Present, Future.” Investigative Genetics, BioMed Central, 2013, obtainable here.

Image Courtesy:

1. “Stages the Gene Fingerprinting” through Sneptunebear16 – Own work-related (CC BY-SA 4.0) via Commons Wikimedia 2. “DNA paternity experimentation en” by Helixitta – own work based on work File:Test na ojcostwo schemat.svg by Pisum (CC BY-SA 3.0) via Commons Wikimedia