Home > Forensics > Performing DNA Typing

Performing DNA Typing

By: Ian Murnaghan BSc (hons), MSc - Updated: 7 Mar 2014 | comments*Discuss
 
Dna Typing Concept Techniques Marker

DNA typing is an important aspect of many fields and applications such as forensic science, medicine and paternity disputes. It goes by many names, including DNA fingerprinting, profiling or testing. The approach is not a singular one, which means that there are numerous techniques used to perform DNA typing. Research is continuously evolving and techniques are regularly refined or replaced by newer, more sophisticated ways to perform DNA typing. While you may be interested to read an overview on the different ways to perform DNA typing or even read in-depth on each technique, it can be helpful to simply get a basic sense of why we even perform DNA typing and how it is so important to a broad range of fields.

Differences Between People

At an extremely simplistic level, DNA typing takes advantage of the fact that we are all different. Your DNA is a unique fingerprint and is not shared with anyone else, with the exception of identical twins and clones. Still, if you look at it in another light, all humans share much of the same DNA. Yet, given how many bases are in DNA, there are still approximately three million bases that are different from one person to another. In fact, it is fascinating to consider that it is roughly one-tenth of just one percent of DNA that is different. These differences are exploited in the laboratory to create a DNA profile of a person. The sample may be taken from a person's hair, blood, body tissue or many other locations. If the DNA typing is meant for a criminal investigation, then the sample would likely be collected at a crime scene and then assessed for certain DNA markers.

Understanding DNA Markers

DNA markers are an important aspect of DNA typing. A scientist or technician will identify DNA markers from a sample by using something called DNA probes, which find a complementary DNA sequence within the sample and then bind to it. A set of probes that will bind to a sequence of DNA will produce a special, unique pattern for a person. By comparing DNA profiles, scientists can then create data that may be useful for applications such as a criminal case. A scientist might check to see if the DNA profile is a match between a suspect in a crime and evidence found at the scene of the crime.

Assessing a Match

It is important to keep in mind that one marker is not considered enough to match up evidence. Of the thirteen regions that differ within humans, one or two markers matching is not considered a strong match but five would be considered reasonably strong and more likely to indicate that the DNA typing is indicative of the same person. It is, however, still a balancing act to assess how strong the DNA typing is with regards to a match. Some scientists cite that DNA typing is more advanced and better than an eyewitness statement.

DNA typing may be a concept with several names and even more techniques, but it will continue to operate on a simple premise, which is that humans are different and these differences can be measured and compared to provide important information.

You might also like...
Share Your Story, Join the Discussion or Seek Advice..
I like the topic of DNA typing.
santi - 7-Apr-11 @ 9:19 PM
Share Your Story, Join the Discussion or Seek Advice...
Title:
(never shown)
Firstname:
(never shown)
Surname:
(never shown)
Email:
(never shown)
Nickname:
(shown)
Comment:
Validate:
Enter word:
Topics
Latest Comments
  • twinkle twinkle
    Re: The Importance of DNA
    The best way to describe the significance of DNA. Thanks
    21 January 2018
  • Bara
    Re: DNA Test after Death
    my brother passed away and was cremated. Is it possible to have his DNA tested using his hair off his clothes that we still have?
    21 January 2018
  • None
    Re: How was DNA Discovered?
    Sorry to read that Ray Gosling (Franklin's PhD student) has not been credited with preparing the DNA for, and then taking, photograph 51.…
    12 January 2018
  • Preston Playz
    Re: An Overview of DNA Functions
    DNA in the body also contains Nucleosides and nucleotides in Which both contains purine and pyridine that are complex compound…
    10 January 2018
  • ExploreDNA
    Re: DNA Test after Death
    Asking - Your Question:Okay I have a friend and she’s pregnant and has a child born her baby father passed away can she test her baby that’s…
    3 January 2018
  • Asking
    Re: DNA Test after Death
    Okay I have a friend and she’s pregnant and has a child born her baby father passed away can she test her baby that’s born to the pregnancy now
    2 January 2018
  • Teri
    Re: DNA Test after Death
    Mother died from cancer. Had treatments for almost year. Was cremated. Possible to still get any DNA from remains. It was 14 yrs ago Family…
    14 December 2017
  • Olas
    Re: Urine Testing for DNA Fragments
    Does dna enter the urine in the form of nucleuoproteins ? Or it enters alone I need explanation plz??
    9 December 2017
  • Lady Vee
    Re: An Overview of DNA Functions
    It's quite true that DNA was discovered by Crick and Watson based on the study I had on other sites... But I'm surprised you made…
    8 December 2017
  • Shakara
    Re: DNA Test after Death
    Hi just wondering on my birth certificate has my mum name and father but before my mum passed she told me he weren't my father so how can i…
    25 November 2017
Further Reading...
Our Most Popular...
Add to my Yahoo!
Add to Google
Stumble this
Add to Twitter
Add To Facebook
RSS feed
You should seek independent professional advice before acting upon any information on the ExploreDNA website. Please read our Disclaimer.