DNA item examination

Question 1

how big does an item need to be to examine

Answer 1

needs to fit in 1.5ml micro centrifuge tube

Question 2

how do you examine cigarette ends

Answer 2

cut out 5mm^2 from paper at smoked end, not filter

Question 3

how do you examine chewing gum

Answer 3

cut out 5mm^3 from gum

easier to handle if frozen

Question 4

how do you examine hairs

Answer 4

need root material
remove 5mm from end
if more than one hair and confident of same type then combine up to 5 roots

Question 5

how do you examine drinks containers

Answer 5

swab around mouthpiece to recover possible saliva

avoid visible staining from drink

Question 6

how do you examine touch DNA

Answer 6

can be sampled from almost any item

need logical approach

Question 7

name 3 sampling methods

Answer 7

double swabbing method-wet and then dry swabs, use distilled water

use tweezers with small pieces of filter paper to get into small spaces

taping for larger, absorbent surfaces