Forensic Serology and Laboratory Accreditation: Key Concepts and Definitions

What is the definition of serology?

The scientific study of serum and other bodily functions.

What is the definition of forensic serology?

The identification and characterization of bodily functions.

Physical evidence can be collected from what?

The crime scene, the victim, and the suspect.

What are the two key biological evidence that can answer the question "who was involved in the crime"?

Fingerprints and DNA.

What is laboratory accreditation?

a team of qualified people come to your lab, inspect the lab, go over policies, procedures, case files, security measures and see if your lab follows the national standard.

What does ASCLD stand for?

American Society of Crime Laboratory Directors

What does ASCLD-LAB stand for?

American Society of Crime Laboratory Directors-Laboratory Acceleration Board

What does FQS stand for?

Forensic Quality Services

What does NFSTC stand for?

National Forensic Science Technology Center

What does CTS stand for?

Collaborative Test Services

What does CAP stand for?

College of American Pathologists

What does SERI stand for?

Serological Research Institute

What does NIST stand for?

National Institute of Standards and Technology

What does ANAB stand for?

ANSI National Accreditation Board

What does ANSI stand for?

American National Standards Institute

What does ASQ stand for?

American Society for Quality

What are the names of private laboratories in Mississippi and elseware?

Scales Laboratory, Legal Genetics, and Ron & Smith Associates

What are the name of some federal laboratories?

FBI, US Postal Service, and DEA (Drug Enforcement Administration

What is a proficiency test?

Test administered to all individuals working in the lab and generating results and reports

What are the names of some agencies that provide proficiency tests?

CTS, CAP, Cellmark, SERI, RTI, American Proficiency Institute

What is Locard's exchange principle?

When two objects come into contact with each other, transfer of materials occurs.

Who wrote the book "Blood Stains: Their Detection and the Determination of Their Source" and what year was it published?

W.D Sutherland; 1907

Blood grouping was discovered in what year and by who?

1901; Karl Landsteiner

What are the two characteristics of hemoglobin crystals?

Pink and feathered shape

Phenolphthalein is a what indicator?

pH

What is the other name for a phenolphthalein test?

Kastle-Meyer color test

What is the oxygen donor in the phenolphthalein test for blood?

Hydrogen peroxide

What is the active ingredient in the Hemastix test strip?

TMB (tetramethylbenzidine)

Blood grouping is based on what and what reaction?

Antigen and Antibody

What are some of the evidence that can provide the answer when and how something happened, and who was involved?

DNA, fingerprints, the witness, the victim (if alive), the crime scene, the suspect confessions, blood, and the medical examiner

What are the names of some government laboratories?

AFT (alcohol, tobacco, and firearms); Army Lab-USARIL; AFDIL (Armed Forces DNA Identification Laboratory)

What are the three manuals required in a serology lab?

1.) Serology Procedures Lab

2.) Serology Training Manual

3.)Serology Quality Control Manual

What is Quality Control?

Documentation after the calibration is complete: when was it done, who did it, and what was the result/value

What is quality assurance?

Written document of how quality is going to be maintained

What are two types of associate evidence and examples?

1.) Class Evidence: part of a limited class along with potential members; ex.) a Nike shoe print

2.) Identification Evidence: fingerprints, DNA, fracture matches, impression evidence from worn out shoes

What are the 4 essential pieces of information that goes on the evidence envelope?

1.) Case Number

2.) Item Description

3.) Date and Time

4.) Collector's Information

What are the three types of tests to determine a body fluid.

1.) Presumptive Test

2.) Confirmatory Test

3.) Species Specificity Test

What is a presumptive test? and provide and example and the body fluid it is used for?

A test that indicates the possible presence of body fluid; cannot be confirmed; used for blood, saliva, and semen

ex.) color development test

What are the two sub-types of presumptive test for blood?

1.) Catalytic Color Test

2.) Chemiluminescence and Fluorescence Test

What are two examples of catalytic color test?

1.) Hemastix

2.) Phenolphthalein

What type of test does luminol belong to?

Fluorescent tests

The presumptive tests are much more sensitive than confimatory tests...true or false?

True

Describe the so called method of paternity testing in the Hsi Yuan Lu complication.

Mix the blood of the parents and child by cutting the finger and allow to drip in basin of water. If it mixes smoothly, they are related. If clumping of cells occur, that indicates non-relatedness.

The Nobel Prize was awarded to Lanstienter for his discovery of what?

Blood grouping

What are the 4 active ingredients in the Takayama reagent?

1.) Pyridine

2.) NaOH

3.) Glucose

4.) Water

What is the scientific name of hemoglobin?

Heme

What are peroxidases?

Enzymes which catalyze the peroxide- mediated oxidation of organic compounds

Write a generalized peroxidase reaction and identify each compound.

AH2+H2O2 -> A +2H2O

AH2= donor (any oxidizable substrate)

A= colored end product

H2O2= hydrogen peroxide

Describe the phenolphthalein reagent preparation in the laboratory; name of chemicals, how it is made, and what happens during the reaction.

Phenolphthalein is oxidized from pink under basic conditions, phenolphthalein under reduced form is colorless; oxidized bu peroxidase in presence of H2O2 (pink appears)

phenolphthalein + H2O2 + Blood > Pink color > Indicative of blood

The Takayama crystal test is also called the what?

Hemochromogen crystal test

What are the similarities and differences of between the chemiluminescence and fluorescence tests?

Differences: chemiluminescence (oxidized) produces light directly while fluorescence (reduced) requires an extra light source

Similarity: Both are a type of presumptive test

How DTT helps in the hemoglobin crystal formation in Takayama crystal test?

It is put in the reaction to reduce the takayama competition and shift the reaction in favor of pyridine

What are the different types of proficiency test?

Internal, external, known, and blind