DNA Analyst Certification Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf
- Which enzyme is primarily used to cut DNA at specific sequences in
- DNA polymerase
- Restriction endonuclease
- Ligase
- Helicase
forensic analysis?
Rationale: Restriction endonucleases cut DNA at specific nucleotide
sequences, which is fundamental in DNA profiling.
- What is the main purpose of the Polymerase Chain Reaction (PCR) in
- Separate DNA strands
- Amplify small DNA samples 1 / 4
forensic DNA analysis?
- Sequence DNA
- Stain DNA
Rationale: PCR allows forensic scientists to make millions of copies of a
small DNA sample for analysis.
- STRs (Short Tandem Repeats) are most useful in forensic DNA profiling
because they:
- Are identical in all humans
- Vary greatly between individuals
- Only appear on the Y chromosome
- Are highly conserved
Rationale: STRs vary significantly between individuals, making them ideal
markers for identification.
4. In forensic DNA analysis, the term “allele” refers to:
- A chromosome
- A variant form of a gene at a specific locus
- An entire genome
- A DNA replication enzyme
Rationale: Alleles are different versions of a gene located at the same locus
on a chromosome.
- Which of the following is a common source of DNA in forensic
- Sweat 2 / 4
samples?
- Hair shaft
- Blood
- Oil
Rationale: Blood contains nucleated cells and is a rich source of DNA for
analysis.
- What is the purpose of electrophoresis in DNA analysis?
- Amplify DNA
- Sequence DNA
- Separate DNA fragments by size
- Denature proteins
Rationale: Electrophoresis separates DNA fragments based on size,
allowing visualization and comparison.
- Which part of the DNA molecule is used to distinguish between
- Phosphate backbone
- Non-coding regions
- Hydrogen bonds
- Ribose sugar
individuals?
Rationale: Non-coding regions, including STRs, show variability between
individuals, which is used in profiling.
- Which term describes a DNA sample that has been contaminated or
degraded? 3 / 4
- High quality
- Purified
- Low template DNA
- Plasmid DNA
Rationale: Low template DNA refers to samples with minimal or degraded
DNA, which require careful handling.
9. Mitochondrial DNA is especially useful in forensic cases when:
- Nuclear DNA is abundant
- Only degraded or hair samples without a root are available
- Blood samples are present
- STR analysis is possible
Rationale: Mitochondrial DNA is more stable and can be used when
nuclear DNA is insufficient or degraded.
10. Y-STR analysis is used primarily to:
- Identify mitochondrial DNA
- Amplify autosomal DNA
- Trace male lineage
- Determine hair color
Rationale: Y-STRs are located on the Y chromosome and are used to track
male-specific lineage.
11. The term “locus” in DNA profiling refers to:
- DNA base pair
- / 4