Mixed Deck — All FDC Topics Flashcards

Which regulatory requirement is UNIVERSAL across all Forensic DNA Certification practice settings?

Answer: Maintaining current certification and continuing education

Maintaining current certification and continuing education is a universal regulatory requirement.

Which organization provides accreditation specifically recognized for forensic DNA laboratories in the United States?

Answer: ASCLD

ASCLD (American Society of Crime Laboratory Directors/Laboratory Accreditation Board) provides the primary accreditation program for forensic laboratories in the US.

How is contamination prevented in forensic labs?

Answer: Use clean workspaces and protocols

Contamination in forensic labs is rigorously prevented through strict adherence to protocols, including the use of clean, designated workspaces, sterile equipment, and personal protective equipment. Separating samples, maintaining one-way workflows, and regular decontamination of surfaces also minimize the risk of transferring foreign DNA. These measures are critical to ensure the integrity of evidence and prevent false or misleading results in forensic investigations.

What is Polymerase Chain Reaction (PCR) used for in DNA analysis?

Answer: To amplify DNA segments

Polymerase Chain Reaction (PCR) is a fundamental technique in DNA analysis used to amplify specific segments of DNA, creating millions of copies from even a tiny sample. This amplification is crucial in forensic science because crime scene evidence often contains only minute amounts of DNA, which would otherwise be insufficient for further analysis. PCR enables the generation of enough material for techniques like STR profiling.

How are quality controls used in forensic labs?

Answer: Verify valid results

Quality controls are indispensable in forensic labs to verify the validity and reliability of testing results. By including known positive and negative samples, labs can confirm that the analytical methods are working correctly, detect potential contamination, and ensure the accuracy of the unknown samples being tested.

Why is transparency important in forensic DNA reporting?

Answer: Promote trust and review

Transparency in forensic DNA reporting is essential to promote trust and allow for independent review of the findings. By clearly documenting methods, assumptions, limitations, and interpretations, forensic reports enable scrutiny by legal professionals and other scientists, reinforcing the credibility and accountability of the forensic process.

When a forensic laboratory receives evidence that lacks proper seals or tamper-evident tape, the CORRECT initial response under standard accreditation protocols is to:

Answer: Accept the evidence and photograph the packaging deficiency, then notify the supervisor and submitting agency before proceeding

Accreditation standards require documentation of the packaging deficiency, photographic record, and notification prior to analysis so that all parties can assess admissibility implications.

A soil-contaminated skeletal remain found outdoors is BEST prepared for DNA analysis using which approach?

Answer: Decontaminate the bone surface mechanically with a Dremel tool, UV irradiate, then sample inner cortical bone powder

Mechanical removal of the outer surface eliminates exogenous DNA, UV irradiation further degrades surface contamination, and sampling the inner cortical powder provides the best-preserved endogenous DNA.

What is the minimum number of STR loci currently required for a CODIS core profile?

Answer: 20

In 2017, CODIS expanded from 13 to 20 core STR loci to improve discrimination power and international compatibility.

When a FDC professional encounters an unexpected result during a procedure, the FIRST action should be to:

Answer: Stop, assess the situation, and determine whether to proceed or seek guidance

Stopping to assess unexpected results is critical for safety and quality.

What is the BEST way for a Forensic DNA Certification professional to stay current with regulatory changes?

Answer: Monitor regulatory bodies, attend CE, and participate in professional associations

Staying current requires monitoring agencies, attending CE, and participating in professional associations.

How should evidence be transported to the lab?

Answer: Secure, contamination-free transport

Evidence must be transported to the lab in a secure, contamination-free manner to maintain its integrity. This involves using sealed, labeled containers and following strict protocols to prevent loss, damage, or cross-contamination, ensuring the evidence remains admissible and reliable for analysis.

What is Short Tandem Repeat (STR) analysis?

Answer: Examining repeated DNA sequences

Short Tandem Repeat (STR) analysis is a widely used forensic technique that examines specific regions of DNA containing short, repeating nucleotide sequences. Individuals inherit a unique number of these repeats from each parent, creating a highly variable and distinctive genetic profile. By analyzing multiple STR loci, forensic scientists can generate a unique DNA profile for individual identification, crucial for linking suspects to crime scenes.

What is a stochastic effect in low-template DNA analysis?

Answer: Random PCR amplification bias that can cause allele dropout, drop-in, or peak height imbalance

Stochastic effects occur with low DNA template quantities and result in random amplification variation, including allele dropout (missing alleles) and drop-in (spurious alleles).

Which scenario represents a violation of the Forensic DNA Certification code of professional conduct?

Answer: Misrepresenting qualifications or certification status

Misrepresenting qualifications is a serious violation that undermines public trust.

What is electrophoresis used for in forensic analysis?

Answer: Separating DNA fragments

Electrophoresis is a fundamental technique in forensic analysis used to separate DNA fragments based on their size. After DNA amplification, such as PCR of STRs, the resulting fragments are loaded into a gel or capillary, and an electric current is applied. This process allows scientists to visualize and differentiate DNA fragments, which is crucial for creating a unique DNA profile for individual identification in forensic investigations.

A FDC professional discovers a conflict of interest in a current assignment. What is the MOST ethical course of action?

Answer: Disclose the conflict immediately and recuse if necessary

Ethical standards require immediate disclosure of conflicts of interest to protect integrity.

In Forensic DNA Certification practice, what is the CORRECT sequence when performing a technical procedure?

Answer: Plan, prepare, execute, verify, and document

The correct sequence follows: plan, prepare, execute, verify, and document.

What is the MOST important reason for Forensic DNA Certification professionals to maintain continuing education?

Answer: To stay current with evolving standards, practices, and regulations

Continuing education ensures professionals remain current with evolving standards and regulations.

The Product Rule in forensic DNA statistics is applied to:

Answer: Multiply individual locus genotype frequencies across multiple STR loci to obtain a combined profile frequency

The Product Rule allows analysts to combine genotype frequencies across independent STR loci by multiplication, yielding the overall profile frequency assuming independence between loci.