QA-QC
Laboratory practices implemented to reduce the risk for contamination.
What are aseptic techniques?
A process that tracks the movement of evidence through its collection, safeguarding, and analysis lifecycle by documenting each person who handled the evidence, the date/time it was collected or transferred, and the purpose of the transfer.
What is a chain of custody?
The primary purpose of this technology is to separate and detect short tandem repeat (STR) alleles.
What is capillary electrophoresis?
The minimum height requirement at and above which detected peaks can be reliably distinguished from background noise; peaks above this threshold are generally not considered noise and are either artifacts or true alleles.
What is the analytical threshold?
A principle used to predict the stability of allele and genotype frequencies from one generation to the next.
What is Hardy-Weinberg Equilibrium?
The formal recognition that a laboratory meets or exceeds a list of standards.
What is accreditation?
The primary purpose of this method is to lyse cells, isolate DNA, and remove inhibitors.
What is extraction?
An enzymatic process in which a specific region of DNA is replicated over and over again to yield many copies of a particular sequence.
What is polymerase chain reaction (PCR)?
A common PCR artifact resulting from strand slippage, typically results in one repeat less than the true allele.
What is stutter?
The genetic equation for a heterozygote.
These standards describe the quality assurance requirements that laboratories performing forensic DNA testing or utilizing the Combined DNA Index System (CODIS) shall follow to ensure the quality and integrity of the data generated by the laboratory.
What are the Quality Assurance Standards (QAS)?
The primary purpose of this method is to determine the amount of amplifiable DNA in a sample.
What is quantitation?
Also known as microsatellite DNA, these can be highly variable among individuals making them effective for human identification purposes.
What are short tandem repeats (STRs)?
A technological artifact observed when the spectral calibration does not properly correct for the spectral overlap between the dyes.
What is pull-up?
The probability of randomly selecting an unrelated individual from the population with the same DNA profile.
What is a random match probability (RMP)?
One of the primary responsibilities of this organization is to serve as a forum to discuss, share, and evaluate forensic biology methods, protocols, training, and research to enhance forensic biology services.
What is the Scientific Working Group on DNA Analysis Methods (SWGDAM)?
The primary purpose of this method is to increase the number of molecules representing a specific target sequence.
What is amplification?
An artificial mixture of the most common alleles present in the human population at each STR locus.
What is an allelic ladder?
The relative proportion of two alleles at a given locus, as determined by dividing the peak height of an allele with a lower relative fluorescence unit (RFU) value by the peak height of an allele with a higher RFU value, and then multiplying this value by 100.
What is a peak height ratio?
The genetic equation for a homozygote.
What is p^2 + p(1-p)theta?
The purpose of this document is to provide a framework for describing ethical and professional responsibilities in the forensic workplace.
What is the Guiding Principles of Professional Responsibility for Forensic Service Providers and Forensic Personnel (GD 3150)?
The process of demonstrating that a laboratory procedure is robust, reliable, and reproducible in the hands of the personnel performing the test in the laboratory.
What is a validation?
DNA fragments with known size added to every sample to correlate electrophoretic mobility to a PCR product size.
What is an internal lane standard (ILS)?
The peak height value below which it is reasonable to assume that, at a given locus, allelic dropout of a sister allele in a heterozygous pair may have occurred.
What is the stochastic threshold?
Refers to loci that are in random association, inherited independently, and not genetically linked (autosomal-STR loci).
What is linkage equilibrium?