Flashcards in Lecture 4: Population genetics Deck (63)
what advantages does a DNA database bring to criminal investigation?
- criminals reoffended
-severity of crimes done increase
-small number of criminals can be responsible for a large number of crimes
what are the two sections of NDNAD?
-profile generated from evidence collected from crime scenes ( full or partial)
-full DNA generated from individuals.
what does a crime scene sample need to contain before it can be uploaded to the NDNAD?
minimum of 4 pairs of numbers and a sex marker
Forensic Information Database Service
what representatives sit on the FIND board?
– National Police Chiefs’ Council (NPCC)
– Home Office who run the NDNAD
– Association of Police and Crime Commissioners (APCC)
– the Chair of the Biometrics and Forensics Ethics Group
– the Forensic Science Regulator (or representative) (FSR)
– the Biometrics Commissioner (or representative)
– representatives from the police and devolved administrations of Scotland and Northern Ireland
The retention of DNA samples is controlled by who?
the Police and Criminal Evidence Act 1984
whats on the NDNAD legislation?
-DNA destroyed after profile, destroyed within 6 months.
-PACE not applied to volunteers missing persons references
-criminal procedure investigations act regulate extension for casework.
Any age convicted for qualifying 2 offence, how long is DNA kept?
Adult convicted of minor 3 offence, how long is DNA kept?
under 18, minor, (give youth caution), of a mini offence, how long id DNA kept?
first offence: 5 years
indefinite, if prison sentence more than 5 years
2nd conviction: indeifnite
whats a speculative search?
If under the PoFA a subject profile cannot be retained, the act does allow for a search to be conducted against the NDNAD.
when can non routine searches be preformed?
performed on crime scene profiles that do not meet the loading requirements.
who developed familial searching?
when is familial searching used?
In 2017/2018, how many familial searches were carried out?
when was familial searching first used, what was the case?
First used in 2003 with the conviction of Craig Harman for manslaughter after throwing a brick off a bridge which hit a lorry killing the driver.
Joseph James deAngelo was part of what case?
Golden State Killer case
When comparison of DNA profiles from evidence and reference samples fail to exclude an individual, what must happen?
statistics must be used to evaluate the significance of the match
what is population genetics?
Population genetics is the study of the causes of observed patterns of inherited genetic variation within populations
what is population genetics used for?
to apply a statistical significance to the value of a match between two DNA profiles
when is population genetics important?
when dealing with variability and uncertainty, especially in a court of law
it must be careful that the rarity of a profile is ___ over estimated
Statistical basis of the evidence is determined using what?
what are the three ways a DNA match can be communicated?
1. Combined Probability of Inclusion (CPI) or Exclusion (CPE)
2. Random Match Probability (RMP)
3. Likelihood Ratio (LR)
This separation of each pair of alleles is _______ from the separation of others
what happening during meiosis produces variation?
____ _______ gives rise to the variation we see due to both independent assortment of alleles and recombination.
what does meiosis produce?
4 individual gametes
meiosis quick steps
. DNA replicates – 2 chromatids
2. Crossing over
3. Meiosis I