Card Set Information
Test Two DNA forensics (chapter 6-9)
What are the 4 DNA Isolation techniques?
What is DNA isolation?
A technique used to extract and separate DNA only from other cell components and foreign materials
What is Chelex Extraction used for and how does it work?
Very small samples
Uses chemical beads, chelex, that collect and bind all non-DNA materials
Not good for RFLP
What is QiaAmp Extraction?
Silica column bases method
Cell/nucleus is lysed and rinsed
What is organic extraction?
Need Large Sample, but maintain quality and quantity better
What is differential extraction?
A technique to isolate DNA from other cell samples mixed with sperm cells
What is reverse dot blot PCR?
Probes are immobilized on a strip and PCR samples are added to the strip
What are the 3 steps of PCR?
What is the marker specific to male DNA?
What things can degrade DNA?
What is star activity?
Non stringent condition for performance of specific enzyme
What is stochastic fluctuation?
Unequal representative of alleles due to sampling errors
What is Preferential amplification?
One allele is amplified more than the other (looks homozygous)
What is a heteroplasmy?
Mixture of samples in a single source
What is the purpose of DNA typing?
To identify if a person is the source of biological evidence
What are two typing systems for profiling?
Detecting continuous alleles (RFLP)
Detecting discrete alleles (PCR)
What are the 3 ways samples show genetic concordance?
Samples are from the same source
Coincidence (2 people have the same genetic profile for a particular marker)
Error in collection and handling of sample
What two genetic models do we use to estimate allele frequency?
What does the frequency estimate?
The evidence profile, not the suspect profile
The evidence profile is then matched
What are the steps used in estimating profile frequency?
Population studies (collect data)
Frequency is tested for departure from H-W and LE
Calculate Genotype frequency
Calculate frequency by multiplication of loci
Why is it necessary to establish the DNA databank?
What is the difference between a databank and database?
bank- all information about the offender and process of handling the case
base- part of the databank
What is required for successful Databank?
Establishing a database for analyzed data