Molecular Autopsies Flashcards
1
Q
Where do we get reference DNA?
A
- Get DNA from person of interest (hair, toothbrush, razors)
- DNA from blood relatives
- Combined DNA Index System (CODIS)
2
Q
Historical method: Restriction Fragment Length Polymorphism analysis (RFLP)
A
- Cut DNA in a sample using a restriction enzyme
- RUn resulting DNA fragments on a DNA gel
- Southern blot-look for specific DNA segments using a complementary probe
- Usually probed for regions known to have variable repeat lengths.
3
Q
Modern method
A
Polymerase chain reaction (PCR) to amplify regions with known short tandem repeats
4
Q
What are the two components of genetics-based forensic medicine
A
- Molecular autopsies
2. Post-mortem pharmacogenetics
5
Q
What are molecular autopsies used for?
A
- investigate sudden, unexplained deaths (SIDS, SCD)
- complement traditional autopsies
6
Q
Ethics of molecular autopsies
A
- can investigate without family consent and may be subject to public disclosure
- Should tissue from autopsies be held onto to test when we know more?
- Should medical examiner share information with family?
7
Q
What is post-mortem pharmacogenetics?
A
- Why did someone die? Given this medicine/drug?
- certain cytochrome P450 alleles increase risk of oxymoron toxicity
8
Q
Case study: infanticide?
A
- neonate died at 13 days of age of morphine toxicity
- mom prescribed codeine for pain post-episiotomy
- mom had duplication of CYP2D6 gene, making her a fast codeine to morhpine metabolizer
- passed through breast milk, lethal to baby
9
Q
Case study: suicide
A
- individuals with two or more copies of CYP2D6 more common in individuals who committed suicide than in those who died natural deaths
- unresponsiveness to antidepressants?
10
Q
Case study: another infanticide?
A
- mother unex[ectedly lost 4 infants
- 1st 2 deaths SIDS
- 3rd pneumonia due to aspiration of amniotic fluid
- 4th revealed plastic bad with baby DNA in kitchen waste
- mother admitted to placing bag over baby face