2. DNA Three billion base pairs in DNA 99.5% similarity among individuals
Genome = total DNA in the cell
5% of genome is encoded = serves as plans for protein synthesis
95% is non-encoded = JUNK ! Maybe…

5. Going to a certain Location (called a Locus) in your DNA…
We find:
Short Tandem Repeats (STRs)
3-7 bp long, repeating throughout a specific stretch of DNA at a particular location
AGTT AGTT AGTT AGTT AGTT AGTT

6. Technique of DNA Typing
Chain Reaction (PCR) and Short Tandem Repeats (STRs)

7. Please draw this!!

8. Intertwined strands of DNA representing segments of two chromosomes
Chromosome segment on the left contains three repeating sequences of T–A–G
Chromosome segment on right has two repeating sequences of T–A–G

9.  Variants of STR TH01
Top DNA strand has six repeats of the STR A–A–T–G
Bottom DNA strand shows eight repeats
This person’s profile would read: TH01 ____ , ______

11. Process of DNA Typing DNA Extraction
Restriction Enzymes >
PCR – copy / amplify
-- Like your body does REPLICATION
Count the STRs at locations in JUNK
Evaluation - Electropherogram

13. Genetic Analyzer Alleles represented as peaks
Electropherogram: Graph representing STRs

14. Electropherogram

15. Statistical estimates: the product rule
0.222 x
0.222 x 2
= 0.1

16. Statistical estimates: the product rule
1 in 10
1 in 22,200 x
1 in 111
1 in 20
= 0.1
1 in 100
1 in 14
1 in 81
1 in 113,400 x
1 in 116
1 in 17
1 in 16
1 in 31,552 x
1 in 79,531,528,960,000,000
1 in 80 quadrillion

17. Process of DNA Typing

19. Human Identity Testing using STRs
Simultaneous Analysis of 10 STRs and Gender ID
Results obtained in less than 5 hours with a spot of blood the size of a pinhead
probability of a random match: ~1 in 3 trillion
Two different individuals
DNA Size (base pairs)
amelogenin
D19 D3 D8
TH01
VWA
D21
FGA
D16
D18 D2

22. Who’s your Daddy? Paternity testing
ABO blood typing-exclude paternity, but cannot confirm paternity
DNA testing can confirm paternity

23. STR Profiling Sensitivity
STR Profiling-can detect 125 picograms
1 picogram = one-trillionth of a gram
One cell has 7 picograms of DNA
18 DNA bearing cells are needed to get a STR profile