Podcast
Questions and Answers
What is the first step in collecting wet body fluids on non-porous surfaces?
What is the first step in collecting wet body fluids on non-porous surfaces?
- Apply distilled water to the stain
- Use a double-tipped swab to collect the stain
- Absorb the stain onto a sterile cotton swab (correct)
- Scrape the stain off the surface
What should be done with the swabs after collecting wet body fluids?
What should be done with the swabs after collecting wet body fluids?
- Use Q-tips to ensure better absorption
- Label the swab box with the location of recovery (correct)
- Compress the swabs to extract more fluid
- Place swabs in a water solution for preservation
For large porous items with wet body fluids, what is the recommended action?
For large porous items with wet body fluids, what is the recommended action?
- Cover the item with distilled water
- Cut out stained areas or submit the entire item (correct)
- Leave the item in its location
- Swab the area without any preparation
How should dried body fluid stains be collected from surfaces?
How should dried body fluid stains be collected from surfaces?
What is a key caution when collecting dried body fluid stains?
What is a key caution when collecting dried body fluid stains?
What is the maximum number of saturated swabs recommended for submission?
What is the maximum number of saturated swabs recommended for submission?
What type of swabs should not be used when collecting body fluids?
What type of swabs should not be used when collecting body fluids?
What is one of the main reasons for collecting stains as dry items when possible?
What is one of the main reasons for collecting stains as dry items when possible?
What is the main purpose of mitochondrial DNA testing?
What is the main purpose of mitochondrial DNA testing?
Which type of DNA testing is specifically utilized for paternity or lineage cases?
Which type of DNA testing is specifically utilized for paternity or lineage cases?
When is the Virginia DNA Data Bank used?
When is the Virginia DNA Data Bank used?
What limitation does Y-chromosome DNA testing have?
What limitation does Y-chromosome DNA testing have?
What type of samples can be included in a criminal paternity or maternity case analysis?
What type of samples can be included in a criminal paternity or maternity case analysis?
What does the term 'mitotype' refer to in mitochondrial DNA testing?
What does the term 'mitotype' refer to in mitochondrial DNA testing?
Why might some DNA profiles not be suitable for searching against the Virginia DNA Data Bank?
Why might some DNA profiles not be suitable for searching against the Virginia DNA Data Bank?
Which statement is true regarding the elimination of contributors from DNA evidence?
Which statement is true regarding the elimination of contributors from DNA evidence?
What identifiable body characteristics can be isolated from fetal tissue that is 10 to 12 weeks old?
What identifiable body characteristics can be isolated from fetal tissue that is 10 to 12 weeks old?
At what gestational age may identifiable body characteristics be challenging to isolate from the fetus?
At what gestational age may identifiable body characteristics be challenging to isolate from the fetus?
What assistance may be required to isolate fetal tissue from maternal tissue?
What assistance may be required to isolate fetal tissue from maternal tissue?
What is a limitation for requesting the analysis of trace DNA evidence for lesser felony crimes?
What is a limitation for requesting the analysis of trace DNA evidence for lesser felony crimes?
What should be done before submitting a large number of items for DNA analysis?
What should be done before submitting a large number of items for DNA analysis?
What factors determine the determination of probative evidence?
What factors determine the determination of probative evidence?
What happens if additional evidence submissions are needed?
What happens if additional evidence submissions are needed?
What type of evidence can still be collected from washed clothing and bedding?
What type of evidence can still be collected from washed clothing and bedding?
What should be done if a Physical Evidence Recovery Kit (PERK) has been collected?
What should be done if a Physical Evidence Recovery Kit (PERK) has been collected?
What must be collected from the suspect's body in a digital penetration case?
What must be collected from the suspect's body in a digital penetration case?
Which item is used to collect known samples for elimination purposes?
Which item is used to collect known samples for elimination purposes?
What should be avoided when collecting swabs from the suspect's fingers?
What should be avoided when collecting swabs from the suspect's fingers?
During the collection of the suspect's clothing, what is recommended?
During the collection of the suspect's clothing, what is recommended?
What types of materials may be found on the suspect’s clothing during collection?
What types of materials may be found on the suspect’s clothing during collection?
What is the main purpose of the Suspect Physical Evidence Recovery Kit (SPERK)?
What is the main purpose of the Suspect Physical Evidence Recovery Kit (SPERK)?
What is required for DNA analysis of misdemeanor offenses that are not sex-related?
What is required for DNA analysis of misdemeanor offenses that are not sex-related?
What must be submitted to the laboratory before conducting a DNA analysis?
What must be submitted to the laboratory before conducting a DNA analysis?
If an item of evidence is wet, what should be noted before submission?
If an item of evidence is wet, what should be noted before submission?
What is the current policy regarding control swabs?
What is the current policy regarding control swabs?
In a sexual assault case, which item should be included in the first submission of evidence?
In a sexual assault case, which item should be included in the first submission of evidence?
What is recommended before submitting evidence from a 'cold case'?
What is recommended before submitting evidence from a 'cold case'?
What should the investigator do if additional evidence is needed after the initial submission?
What should the investigator do if additional evidence is needed after the initial submission?
Which type of evidence is specifically mentioned as not requiring analysis?
Which type of evidence is specifically mentioned as not requiring analysis?
Study Notes
DNA Testing
- Examiners use statistical calculations to determine if a DNA profile from evidence matches a known sample.
- Mitochondrial DNA testing improves the reliability of identification.
- Mitochondrial DNA testing is used in missing persons and body identification cases.
- Mitochondrial DNA testing is also used in serious felony investigations when other methods yielded limited results.
- Y-chromosome DNA testing is used in cases with high ratios of female DNA to male DNA.
- Y-chromosome DNA testing is used to determine lineage such as paternity or missing persons cases.
- Y-chromosome DNA testing does not yield searchable profiles and is not useful without known reference samples.
Virginia DNA Data Bank
- Evidence profiles that do not match known samples will be searched against the Virginia DNA Data Bank and nationally.
- DNA profiles from mixtures (more than one person) and partial profiles are not suitable for the Virginia DNA Data Bank.
Criminal Paternity/Maternity
- Forensic Biology performs DNA analysis in incest or rape cases that resulted in a child.
- Blood or buccal (cheek) samples from the victim, suspect, and child are sent for comparison.
Wet Body Fluids on Non-Porous Surfaces
- Wet stains should be collected with sterile cotton swabs until saturated.
- Do not use double-tipped swabs or Q-tips.
- Place saturated swabs in a swab box labeled with the location of collection.
Wet Body Fluids on Porous Surfaces
- Submit the air-dried item of evidence if possible.
- Cut out stained areas for large items.
- Swab the stained area with sterile swabs, concentrating the stain as much as possible.
Dried Body Fluids Stains
- Submit the item of evidence whenever possible.
- Swab stains and submit the swabs to the laboratory.
- For large items, cut out stained areas or recover stains with moistened sterile swabs.
Clothing and Bedding
- Submit even washed clothing and bedding if other evidence does not yield probative information.
- Consult with the lab prior to submitting bedding or similar items.
Suspect Physical Evidence Recovery Kit (SPERK)
- SPERK is used within 24 hours of a sexual assault.
- Collect a buccal sample from the suspect for comparison with foreign secretions and hairs from the victim.
- Collect foreign secretions and trace evidence from the suspect's body and underpants.
Sexual Assault Suspect’s Clothing
- Collect the suspect’s clothing worn during the assault.
- Have the suspect stand on a clean sheet of paper while disrobing to collect trace evidence.
Buccal Swabs Kit
- Used to collect known samples from a victim, suspect, or third party for elimination purposes.
Fetal Tissue
- Submit tissue collected from an aborted fetus.
- Tissue from an aborted fetus may be 10 to 12 weeks old and contain identifiable body characteristics.
- Assistance from a medical professional may be required to isolate fetal tissue from maternal tissue.
- Refrigerated tissue should be submitted quickly.
General Reminders
- Requests for analysis of potential “trace” DNA evidence are limited to two samples per case for lesser felony crimes.
- Prior to submitting a large amount of evidence, contact a DNA examiner/supervisor to identify the items most relevant to the case.
- Submit only the most probative items.
- Consult with a Forensic Biology Section examiner or supervisor when submitting evidence from a cold case.
- If evidence cannot be dried before submission, indicate on the RFLE form that the item is wet.
- Do not submit control swabs.
- DNA analysis of evidence associated with misdemeanor offenses will only be analyzed based on a written request from the Commonwealth’s Attorney.
- Submit all appropriate known samples before the DNA analysis of evidence.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz explores the critical aspects of DNA testing, focusing on methodologies such as mitochondrial and Y-chromosome testing. Learn how these techniques are applied in criminal investigations, missing persons cases, and paternity testing. Additionally, it discusses the role of the Virginia DNA Data Bank in evidence matching and profile searching.
