DNA Analysis in Fire Scenes

• Nask / Biologie
• Middelbare school
• vwo
• Leerjaar 6

November 2017

DNA Analysis in Fire Scenes

Milou Hekhuizen, MSc

Lecturer Forensic Laboratory Science &  IT project manager

3 locations 

Breda, Tilburg, Den Bosch

Faculty of Technology of Health and Environment

1500 students 

4 bachelor programs:

(incl. Chemistry, Biology and Forensic Laboratory Research)

How to identify a person?

Can you identify this person?

Could you identify the person you saw in the image?

1. Yes, most likely
2. Yes, definitely
3. No
4. I don't know

DNA analysis

- DNA structure 

- Genomic DNA

- STR analysis

- mtDNA

-Y-DNA

- Discovery & identification of human remains

- From scene to trial

Genomic DNA

DNA strand

3 billion nucleotides

- Guanine

- Cytosine

-Thymine

-Adenine

0.1- 0.4% difference

(99.6-99.9% the same)

Could we use genomic DNA to identify this person?

Could we identify this person using genomic DNA?

1. Yes
2. No
3. Maybe

STR analysis

Set of STR's  = 

unique combination

Polymerase Chain Reaction (PCR)

- Copy specific pieces of DNA

* Make use of copy mechanisms of bacteria

- Exponential amplification

Fluorescent label

Inherit 2 chromosomes

same STR --> different lengths

DNA profile

NL: 12 loci

7 loci by European standards

Treaty of Prüm
matching rules

Why mtDNA?

- many mitochondria

- maternally inherited

- small piece of DNA

Drill or grind

Collect powder

HV1 & HV2

Cambridge reference sequence

Single nucleotides

Cambridge reference

List variations

Check variations with 

references

Polymorphisms

Y-chromosomal DNA

Paternally inherited

Passed on unchanged

(but with gradual 

accumulation of mutations)

STR analysis

Example use of Y-DNA

Marianne Vaatstra (1999)

Traces of blood and semen found

DNA profilling in 2012

Jasper S --> brother's DNA was tested

Marianne Vaatstra

Milica van Doorn

Fire scenes

What are the risks in the investigation of a fire scene?

Risks & difficulties

- Fire debris

- Discovery & identification human remains

Calcined bone

- Brittle

- Grey-ish color

- Fragmented pieces

- >250 degrees Celcius: no amplification possible

Any questions?

Thank you for your attention and participation. What did you think about this lecture?

More info about the minor or internships?

Send an email to Milou Hekhuizen:

[e-mail]

Visualization

- Fluorescent labels/dye

- Within amplified piece of DNA

Sequencing

- To find genes

- Human genome project

- Too much for personal identification (in the case of a crime)