DNA Fingerprinting – Online Make Up Module
Read along in your lab handout with the information in this webpage. Fill in and answer all questions accordingly in the handout. This handout will be collected and graded later.
Lab handout for DNA Fingerprinting – Online Make Up Module
Important Background Information to review:
An Introduction to the Human Genome – Basic Structure and Variation in Human DNA (5:32)
Restriction Enzymes and how they are used with DNA – show how DNA with Restriction Enzymes/Endonucleases and how strands can be put back together with DNA Ligase (another enzyme).
Polymerase Chain Reaction(opens in new window) (PCR) 3D Animation Cold Springs Harbor – click on video – used to make larger samples of DNA from an initial small sample of DNA.
PCR Animation(opens in new window) – a nice simple step by step animation to show how PCR works.
DNA Fingerprinting using PCR (opens in new window)to isolate and amplify Short Tandem Repeats (STR) in small DNA samples, then what they look like separated by DNA Electrophoresis. (4:09)
DNA Gel with labeled known DNA fragment sizes (lane 1). This also shows the different banding pattern results (different sized fragments) produced when using different restriction enzymes on the same DNA.
DNA Electrophoresis Equipment:
How DNA Electrophoresis works – the electrophoretic process.
Activity 1; Practice Pipetting – short videoclips
Activity 2: Restriction Digestion of DNA – view the background Information animations above.
Activity 3 & 4: Preparation of the 0.8% Agarose Gel and Electrophoresis Unit and Preparing the DNA Samples and Loading the Gel
In Activity Three, calculate and record the amount of agarose needed to make the indicated 0.8% agarose gels.
Casting an Agarose Gel – we will actually use a casting stand instead of tape to seal the gel tray.
Loading an Agarose Gel – tips for loading gels and what not to do.
DNA Electrophoresis Procedure – loading and running an agarose gel (as you would have done in lab with the same equipment).
Staining Agarose Gels with Fast Blast Blue – In our teaching labs, we do not use Ethidium Bromide in our gels (it is a highly toxic mutagen and possible carcinogen) as indicated in the DNA Electrophoresis animations in the Background Information above. Instead we will use a non-toxic Fast Blast Blue stain that will bind to the DNA in the gels allowing us to visualize the bands of DNA.
Activity 5: Analyzing the DNA Patterns
- In our lab we will look at the PCR products from DNA left on the glass case compared to samples from 2 probable suspects and a negative DNA control sample. Why is it important to include a negative control on the gel?
- Which of the samples/suspects match the DNA left on the glass case?
- Sketch the stained DNA gel below and label the lanes. Answer the end of lab Discussion Questions #2-5 in your lab handout based upon this gel.
- We can look more closely at the size of sample DNA bands/fragments by comparing the distance traveled in the gel to the known base pair size of the fragments found in the known DNA Standards/Marker DNA. This particular gel does not contain DNA Standards/Marker DNA, but an example of Lambda HindIII DNA size Marker is included below.
| Stained BIORAD DNA Gel (click on image to enlarge) | Stained BIORAD DNA Gel (lanes right to left) | Lambda HindIII DNA size Marker/standard* |
 | Lane 1 = left empty/blank Lane 2 = left empty/blank Lane 3 = No DNA, control Lane 4 = Early bidder Lane 5 = Employee Lane 6 = Evidence from glass Lane 7 = left empty/blank Lane 8 = left empty/blank |  |
* depending on how long a gel is run, you may or may not see all the possible bands of DNA separate.
How DNA Electrophoresis is used in forensics – Nice new webpage – topics include: Can DNA Demand a Verdict? How can DNA be used to identify an individual? Forensic DNA Analysis. Is DNA Analysis alone enough to acquit or convict?
Who Stole the Crown Jewels? – a paper simulation will be performed in place of an actual in lab DNA electrophoresis. (Carry out this simulations and add it to your lab handout)
- From this handout you will need to “add” the restriction enzyme to cut the long DNA sequences for each of the DNA samples on page 5. This Restriction enzyme will find sequences CCGG and cut between the C and G as shown in the example.
- Then count and label the # of base pairs (bp) in each of the new DNA fragments.
- Sketch where these fragment will end up on the DNA gel diagram (page 4) comparing to the known bp units listed on the right of the paper gel. Ignore the 12 bp fragment on the diagram. This is just to show location.
- Examine your completed paper gel and answer question #6 at the end of your DNA Lab Unit Handout.
- Be sure to include the completed pages 4, 5 & 6 with your DNA Unit handouts. You will need to refer to these completed pages to support your answers to #6. You will not get credit for #6 if these completed pages are not provided and legible.
Be sure to insert this activity into your DNA Fingerprinting lab unit.
* If you do not have a printer, you can write down the size for all the fragments for each of the subjects in your handout. Then sketch a labeled diagram of the resulting gel and explain your evidence for who stole the crown jewels.
Basic DNA Structure
Molecular Visualization of DNA – do not worry if you have not covered all of these topics in lecture yet. The animation will be helpful when you do review this material.
0-1:48 = DNA Structure — Also seen in the Mitosis and Meiosis lab (this part is important for lab this week)
The rest of this video with be taught later in lecture and be more applicable in the Transformation lab.
1:48-2:53 = DNA Replication –Can you relate this to DNA synthesis? = S phase that you leaned about in the Mitosis and Meiosis in lecture
2:53-4:48 = Transcription – (you will learn about this and Translation later in lecture)
4:48-6:57 = Translation –
6:58-7:47 = Hemoglobin and Sickle Cell Anemia -not narrated
Modern Molecular Techniques Assignment
Click for details. This assignment will be due by Friday 11:59PM of the Off Lab week following the In Person DNA Fingerprinting Lab. – assignment will be linked here.
Group Work Peer Evaluation form(opens in new window) – each student should complete their own peer review and submit it on Moodle by the same due date as the Modern Molecular Techniques Assignment above. Late Peer Reviews will not be graded. You must indicate your own contributes on the peer review form to receive credit.
Final Pathogen Projects due for next In Person lab week.
Groups will present their Pathogen Project to the class. This will be recorded for self reflection. The final Pathogen paper is also due by the start of that In Person lab week. Click for details. Scroll down to the bottom of the Projects page.
Interesting Molecular Biology courses and opportunities at NCSU
Opportunities for students:
- Minor in Biotechnology at NCSU(opens in new window) (BIT Program) and Courses in Biotech (BIT Spring 2027 & Fall 2026(opens in new window)
- Minor in Biomanufactoring at NCSU (BTEC)
- NCSU Professional Sciences Master’s Degree(opens in new window) (MMB Program – Master’s of Microbial Biotechnology)
- Biomanufacturing on a larger scale at BTEC (on Centennial Campus, click on Academic Programs to learn about available Undergraduate Programs )
Important Technologies in Molecular Biology
How DNA Electrophoresis is used in forensics(opens in new window) – Nice new webpage – topics include: Can DNA Demand a Verdict? How can DNA be used to identify an individual? Forensic DNA Analysis. Is DNA Analysis alone enough to acquit or convict?
DNA Profiling: Tracing Killers and Solving Mysteries Using Genetic Clues – nice article with overview of the development of DNA fingerprinting technologies linked to real cases.
Early ideas and Development of PCR(opens in new window) – A Not So Simple Idea
All About PCR(opens in new window) – A good website with animations and interesting examples
Genome Editing with CRISPR-Cas9 a new and powerful technology with many applications.
Gene Editing Tool CRISPER Wins the Chemistry Nobel(opens in new window) (2020)
ELISA Anitbody tests(opens in new window) – animation that shows the different steps involved in ELISA testing for the presence of antibodies.
Gene Transformation(opens in new window) – inserting new genes/transformation -former BIO 183 lab unit
Bioprocessing – Protein Production and Purification on an Industrial Scale
Careers in Biotech – nice website. (opens in new window) Careers at the Bench and Beyond
Short Reads:
The History of Genetic Fingerprinting
NCSU Researchers Irish Potato Famine Pathogen Stoked Outbreaks on 6 Continents(opens in new window) – using a more specialized electrophoretic genotyping
DNA “Fingerprint” Can Aid Food Safety – NCSU researcher