1. DNA Identification Where does DNA come from? What is it?
1/2 from mom
1/2 from dad
What is it?
“Blue print” of life
How is DNA different among us?
Common vs Different
What does “DNA” mean?
Deoxyribonucleic Acid

2. Where can DNA be found? SAME Cell Cell Types Blood Hair Roots Saliva
Sweat
What does DNA mean? DNA stands for deoxyribonucleic acid. This is just a big name for describing what DNA is made up from. Where can DNA be found? DNA is found in virtually all of our cells.
Some examples of where cells are found are blood, hair roots, saliva, sweat, semen and various tissues. All the DNA from one individual will be the same no matter what cells are looked at. Thus, the DNA from blood will be the same as that from muscle.
Semen
Various Tissue

3. Types of objects where DNA may be found
Blood Stains
Semen Stains
Chewing Gum
Stamps & Envelopes
Penile Swabs
Sweaty Clothing
Bone
Hair
Fingernail Scrapings
Saliva
Where does DNA come from? DNA comes from your mother and father. Half from each. This DNA comes from your parents in the form of a Chromosome. A chromosome is the way the DNA is packaged. Like you would place something in a box to keep it all together. The chromosome would be the box and the DNA would be inside the chromosome.

4. Where is DNA in the body? Cell Nucleus
Where does DNA come from? DNA comes from your mother and father. Half from each. This DNA comes from your parents in the form of a Chromosome. A chromosome is the way the DNA is packaged. Like you would place something in a box to keep it all together. The chromosome would be the box and the DNA would be inside the chromosome.

5. Where types of DNA are found in a cell?
Mitochondrial DNA
Nuclear DNA

6. Where is DNA in the body? Nucleus Paternal Chromosome Maternal
Where does DNA come from? DNA comes from your mother and father. Half from each. This DNA comes from your parents in the form of a Chromosome. A chromosome is the way the DNA is packaged. Like you would place something in a box to keep it all together. The chromosome would be the box and the DNA would be inside the chromosome.
Maternal
Chromosome
Paternal
Chromosome

7. Where is DNA in the body? Chromosome DNA
Where does DNA come from? DNA comes from your mother and father. Half from each. This DNA comes from your parents in the form of a Chromosome. A chromosome is the way the DNA is packaged. Like you would place something in a box to keep it all together. The chromosome would be the box and the DNA would be inside the chromosome.

8. DNA- What it looks like Double Helix Units A =Adenine A T T =Thymine GC
T =Thymine
G =Guanine
DNA:
- double stranded molecule
- made of four bases
- Sugar phosphate backbone
- blue print of life and is the same in all nucleated cells
- combination of the bases that determines a persons genetic make up
- everybody’s genetic make up is different except for identical twins
- inherited 1/2 from mother and 1/2 from father
C =Cytosine

9. STR 4 6 DNA Profile =4,6 5 7 DNA Profile =5,7 Short Tandem Repeat AGAT
TCTA
TCTA
TCTA
TCTA
TCTA
TCTA
TCTA
DNA Profile =5,7

10. Isolation of DNA Blood Hair Roots Saliva Sweat Tissue Chemical DNA
The isolation process consists of taking part of the evidence say from a bloodstain or vaginal swab and placing it into a tube. I will then add some chemicals that will break open the cells and allow me to get the DNA. In the case of a vaginal swab sample I will continue to get the DNA from the sperm by adding a different chemical. Since sperm have a different outer coating I am able to separate the female cells from the male cells.

11. Differential Isolation of DNA
Semen stain
Epithelial DNA
Sperm DNA
Chemical
Semen stain
Different Chemical
Remove
Epithelial
DNA
Sperm
DNA

12. Amplification
(making copies)
DNA
Solution

13. DENATURE
Step one of a single cycle G T A C
Heat T G C A

14. ANNEAL
Step two of a single cycle A T G T A C

15. EXTEND
Step three of a single cycle C A G T A T G A T G A T A C

16. PCR (Polymerase Chain Reaction)
Amplification
PCR (Polymerase Chain Reaction)
5 Cycles
28 Cycles
DNA
4 Cycles
3 Cycles
2 Cycles
1 Cycle
The amplification or copy making of the DNA is what makes PCR so useful. I can start out with a small amount of DNA and after a bunch of cycles have a large amount of DNA.

17. Analysis of amplified DNA
Profile

19. Evidence
Area 1
Area 2
Area 3
Area 4
Area 5
AREAS OF DNA
SAMPLE
Sex
Area 6
15,16
16,17
20,23
X,Y
12,14
30,30
13.2,15
Ref.Std.2
Ref.Std.1
15,16
16,17
20,23
12,14
30,30
X,Y
13.2,15
14,15
17,18
23,24
13,13
X,X
15,19
14,15
17,18
23,24
13,13
30,30
X,X
15,19

20. STR results
The DNA from the evidence stain and the reference sample from the suspect match.
The frequency of this matching pattern is approximately 1 in 520,000,000,000 in the Caucasian population, 1 in 618,500,000,000 in the African American population and 1 in 532,000,000,000 in the Hispanic population.
Based on these results the suspect is the source of the evidence stain to a reasonable degree of scientific certainty.