SerologySerology

O’ConnorO’Connor

Typing of BloodTyping of Blood

Historically significant!Historically significant! Karl Landsteiner earned the Nobel Prize Karl Landsteiner earned the Nobel Prize

for his 1901 discovery.for his 1901 discovery. First to recognize that all human blood First to recognize that all human blood

was not the same; it was distinguishable was not the same; it was distinguishable by group or type.by group or type.

A-B-O SystemA-B-O System

First classification system First classification system Allowed us to match donor to recipient. Allowed us to match donor to recipient.

(saving millions of lives)(saving millions of lives) This opened a new field of research This opened a new field of research By 1937 the Rh factor in blood was By 1937 the Rh factor in blood was

discovered allowing for further discovered allowing for further classification.classification.

Additional FactorsAdditional Factors

Up to 100 different blood factors have been Up to 100 different blood factors have been identified, A-B-O is still the most important.identified, A-B-O is still the most important.

Used to identify individuals based on blood- Used to identify individuals based on blood- in theory no two people (outside of in theory no two people (outside of identical twins) have the same combination identical twins) have the same combination of blood factors.of blood factors.

Significant ~ because crime scenes, in Significant ~ because crime scenes, in particular those of a serious nature like particular those of a serious nature like homicide, assaults & rape are likely to have homicide, assaults & rape are likely to have bloodstains left behind.bloodstains left behind.

DNA and Blood stainsDNA and Blood stains

DNA technology has altered the DNA technology has altered the approach of forensic scientists approach of forensic scientists toward the individualization of toward the individualization of bloodstains & other biological bloodstains & other biological evidence.evidence.

Identifying blood factors has become Identifying blood factors has become obsolete. We now look for DNA, obsolete. We now look for DNA, genetic information.genetic information.

What is blood?What is blood?

Highly complex mixture of cells, Highly complex mixture of cells, enzymes, proteins and inorganic enzymes, proteins and inorganic substances.substances.

The fluid portion is called plasma, The fluid portion is called plasma, composed principally of water & accounts composed principally of water & accounts for 55% of the blood content.for 55% of the blood content.

Solids (45% of blood) are suspended in Solids (45% of blood) are suspended in the fluid, primarily consisting of the fluid, primarily consisting of erythrocytes (red blood cells), leukocytes erythrocytes (red blood cells), leukocytes (white blood cells), and platelets. (white blood cells), and platelets.

ClottingClotting

Blood clots when a protein in the Blood clots when a protein in the plasma known as fibrin traps and plasma known as fibrin traps and meshes the red blood cells.meshes the red blood cells.

If the clotted material were removed, If the clotted material were removed, a pale yellowish liquid known as a pale yellowish liquid known as serum would be left.serum would be left.

Forensics & BloodForensics & Blood

For forensics we are concerned with red For forensics we are concerned with red blood cells & blood serum.blood cells & blood serum.

On the surface of red blood cells are On the surface of red blood cells are millions of characteristic chemical millions of characteristic chemical structures called antigens.structures called antigens.

(a substance, usually a protein, that (a substance, usually a protein, that stimulates the body to produce stimulates the body to produce antibodies against it) More than 15 blood antibodies against it) More than 15 blood antigens have been identified. The A-B-O antigens have been identified. The A-B-O and Rh systems are the most important.and Rh systems are the most important.

Blood TypingBlood Typing

Type A blood indicates the cell has A Type A blood indicates the cell has A antigens on its surface. (AB has some of antigens on its surface. (AB has some of both) (Type O has neither A or B both) (Type O has neither A or B antigens)antigens)

The Rh factor is also referred to as the D The Rh factor is also referred to as the D antigen. If it’s present you are Rh+, if you antigen. If it’s present you are Rh+, if you don’t you are Rh-don’t you are Rh-

SerumSerum

Serum contains proteins known as antibodies. Serum contains proteins known as antibodies. (For every antigen there exists a specific (For every antigen there exists a specific antibody) antibody)

Naming antibodies, start with prefix anti- and Naming antibodies, start with prefix anti- and add the name for the antigen; example anti-Badd the name for the antigen; example anti-B

A serum that contains antibodies is known as A serum that contains antibodies is known as an antiserum. (it reacts against antigens- only an antiserum. (it reacts against antigens- only the specific one it is named for)the specific one it is named for)

Antibodies are bivalent- meaning they have 2 Antibodies are bivalent- meaning they have 2 reactive sites. Allows for them to link up, like in reactive sites. Allows for them to link up, like in chains and is usually seen as clumping or chains and is usually seen as clumping or agglutination.agglutination.

Antibody Agglutination

Human Blood Type Chart - A, B, AB or OHuman Blood Type Chart - A, B, AB or O

ABOABOBlood TypeBlood Type

Per Cent Per Cent of of

General General PopulatioPopulatio

nn

CanCanDONATEDONATE

Red Cells To:Red Cells To:

CanCanRECEIVERECEIVE

Red Cells From:Red Cells From:

Chance of Chance of Finding A Finding A

Compatible Compatible DonorDonor

O+O+ 38.5%38.5% O+, A+, B+, O+, A+, B+, AB+AB+ O+, O-O+, O- 1 out of 21 out of 2

50% 50%

O-O- 6.5%6.5%All TypesAll Types(universal (universal

donor)donor)O-O- 1 out of 151 out of 15

7% 7%

A+A+ 34.3%34.3% A+, AB+A+, AB+ A+, A-, O+, O-A+, A-, O+, O- 4 out of 54 out of 580% 80%

A-A- 5.7%5.7% A-, A+, AB-, AB+A-, A+, AB-, AB+ A-, O-A-, O- 1 out of 81 out of 813% 13%

B+B+ 8.6%8.6% B+, AB+B+, AB+ B+, B-, O+, O-B+, B-, O+, O- 3 out of 53 out of 560% 60%

B-B- 1.7%1.7% B-, B+, AB-, AB+B-, B+, AB-, AB+ B-, O-B-, O- 1 out of 121 out of 129% 9%

AB+AB+ 4.3%4.3% AB+AB+All TypesAll Types(universal (universal recipient)recipient)

  100%100%

AB-AB- 0.7%0.7% AB-, AB+AB-, AB+ AB-, A-, B-, O-AB-, A-, B-, O- 1 out of 71 out of 714% 14%

Mixing the wrong bloodsMixing the wrong bloods

There are fatal consequences for There are fatal consequences for mixing the wrong blood types. It is mixing the wrong blood types. It is why blood transfusions must be type why blood transfusions must be type specific.specific.

O is a universal donor – it won’t react O is a universal donor – it won’t react badly with A, B or AB. badly with A, B or AB.

SerologySerology

The study of antigen-antibody The study of antigen-antibody reactions.reactions.

The most wide spread application of The most wide spread application of Serology is the typing of whole blood Serology is the typing of whole blood for A-B-O identity.for A-B-O identity.

The generalized population The generalized population distribution:distribution:

OO AA BB ABAB 43%43% 42%42% 12%12% 3%3%

Immunoassay TechniquesImmunoassay Techniques

Serology has expanded to detection Serology has expanded to detection of drugs in blood & urine.of drugs in blood & urine.

Antibodies that react with drugs Antibodies that react with drugs don’t exist naturally but can be don’t exist naturally but can be created in animals such as rabbits.created in animals such as rabbits.

UrinalysisUrinalysis

Test to determine if drugs are Test to determine if drugs are present.present.

Immunoassay testing for drugs has Immunoassay testing for drugs has proven quite suitable for large proven quite suitable for large volumes of specimens.volumes of specimens.

Immunoassay tests are only Immunoassay tests are only presumptive in nature & results must presumptive in nature & results must be confirmed by additional testing.be confirmed by additional testing.

Radioimmunoassay (RIA)Radioimmunoassay (RIA)

Uses drugs labeled with radioactive Uses drugs labeled with radioactive tags. (ex. EMIT)tags. (ex. EMIT)

They are not totally specific to any They are not totally specific to any one drug. (This can hinder a case like one drug. (This can hinder a case like it did in the Dr. Mario E. Jascalevich it did in the Dr. Mario E. Jascalevich from ch. 1) from ch. 1)

Forensic Characterizations of Forensic Characterizations of BloodstainsBloodstains

Criminalists must answer the following Criminalists must answer the following questions:questions:

1. Is it blood?1. Is it blood? 2. From what species did the blood 2. From what species did the blood

originate?originate? 3. If human, how closely can it be related 3. If human, how closely can it be related

to a particular individual?to a particular individual?

Color TestsColor Tests

Phenolphthalein is generally used now and Phenolphthalein is generally used now and it’s known as the Kastle-Meyer color testit’s known as the Kastle-Meyer color test

It identifies not only blood, but some It identifies not only blood, but some vegetables like potatoes & horseradish.vegetables like potatoes & horseradish.

It is highly indicative of blood & is used by It is highly indicative of blood & is used by field investigators.field investigators.

Hemastix strips are useful indicators- Hemastix strips are useful indicators- moisten with distilled water and placed in moisten with distilled water and placed in contact with bloodstains a green color will contact with bloodstains a green color will appear to indicate blood.appear to indicate blood.

LuminolLuminol

Presumptive ID test for blood. Presumptive ID test for blood. It doesn’t change color, it produces light. It doesn’t change color, it produces light.

You spray it on and turn off the lights, if You spray it on and turn off the lights, if the stain is blood it will have a faint blue the stain is blood it will have a faint blue glow (luminescence). glow (luminescence).

Extremely sensitiveExtremely sensitive Does not interfere with DNA testingDoes not interfere with DNA testing Used for large areas like carpet, inside of Used for large areas like carpet, inside of

a car, walls, etc.a car, walls, etc.

Microcrystalline TestsMicrocrystalline Tests

Two most popular:Two most popular: Takayama testTakayama test Teichmann testTeichmann test

Form crystals when mixed w/ bloodForm crystals when mixed w/ blood Less sensitiveLess sensitive subject to interference of contaminantssubject to interference of contaminants

Precipitin TestPrecipitin Test

Once known to be blood, this test is used Once known to be blood, this test is used to determine, human or animal in origin.to determine, human or animal in origin.

Add human antiserum and the blood Add human antiserum and the blood sample in a tube- if human a cloudy ring sample in a tube- if human a cloudy ring or band will appear where the two or band will appear where the two substances meet.substances meet.

Gel Diffusion is another type of Precipitin Gel Diffusion is another type of Precipitin testtest

Gel DiffusionGel Diffusion

You test in an agar plate.You test in an agar plate. Two holes are made in agar, opposite of Two holes are made in agar, opposite of

each other and add the sample to one & each other and add the sample to one & antiserum to the other.antiserum to the other.

If they move towards each other across the If they move towards each other across the gel agar, then it is positive for human blood.gel agar, then it is positive for human blood.

Can also be done through electrophoresis- Can also be done through electrophoresis- using electrical current to draw them using electrical current to draw them together.together.

Highly sensitive & requires a small sampleHighly sensitive & requires a small sample

Bloodstain Pattern AnalysisBloodstain Pattern Analysis

is the examination of the shapes, is the examination of the shapes, locations, and distribution patterns locations, and distribution patterns of bloodstains, in order to provide of bloodstains, in order to provide an interpretation of the physical an interpretation of the physical events which gave rise to their events which gave rise to their origin.origin.

Based on the premise that all Based on the premise that all bloodstains and bloodstain bloodstains and bloodstain patternspatternsare characteristic of the forces that are characteristic of the forces that have created them.have created them.

The determinations made from bloodstain The determinations made from bloodstain patterns at the scene or from the clothingpatterns at the scene or from the clothing

of principals in a case can be used to:of principals in a case can be used to: Confirm or refute assumptions concerning

events & their sequence:Position of victim. (standing, sitting, lying)Evidence of a struggle. (blood smears, blood trails)

Confirm or refute statements made by principals in the case:Are stain patterns on a suspects clothing consistent with his reported actions?Are stain patterns on a victim or at a scene consistent with accounts given by witnesses or the suspect?

Blood VolumeBlood Volume

On average, accounts for 8 % of total body weight

5 to 6 liters of blood for males 4 to 5 liters of blood for females

A 40 % blood volume loss, internally or/and externally,is required to produce irreversible shock (death).

A blood loss of 1.5 liters, internally or externally, is required to cause incapacitation

Surface TensionSurface Tension

The elastic like property of the The elastic like property of the surface of the liquid that makes it surface of the liquid that makes it tend to contract,tend to contract,caused by the forces of attraction caused by the forces of attraction between the molecules of the liquid.between the molecules of the liquid.

The cohesive forces tend to resist The cohesive forces tend to resist penetration and separation.penetration and separation. (blood (blood drops will tend to stay clumped together)drops will tend to stay clumped together)

Categories of BloodstainsCategories of Bloodstains PASSIVEPASSIVE

TRANSFERTRANSFER

PROJECTEDPROJECTED

TRANSFER BLOODSTAINSTRANSFER BLOODSTAINS A transfer bloodstain is created when a

wet, bloody surface comes in contact with a secondary surface.

A recognizable image of all or a portion of the original surface may be observed in the pattern,as in the case of a bloody hand or footwear.

Transfer bloodstains can be further subdivided into; Contact bleeding Swipe or Smear Wipe Smudge

PASSIVE BLOODSTAINSPASSIVE BLOODSTAINS

Passive Bloodstains are drops created or formed by the force of gravity acting alone.

This category can be further subdivided to include;

Drops Drip patterns Pools Clots

TARGET SURFACE TEXTURETARGET SURFACE TEXTURE Bloodstains can occur on a variety of surfaces, Bloodstains can occur on a variety of surfaces,

such as carpet, wood, tile, wallpaper,such as carpet, wood, tile, wallpaper,clothing, & the list goes on……clothing, & the list goes on……

The type of surface the blood strikes affects the The type of surface the blood strikes affects the amount of resulting spatter,amount of resulting spatter,including the size & appearance of the blood including the size & appearance of the blood drops.drops.

Blood droplets that strike a hard smooth surface, Blood droplets that strike a hard smooth surface, like a piece of glass, will have little or no like a piece of glass, will have little or no distortion around the edge.distortion around the edge.

Blood droplets that strike linoleum flooring take on a slightly different appearance. Notice the distortion (scalloping) around the edge of the blood droplets.

Surfaces such as wood or concrete are distorted to a larger extent. Notice the spines& secondary splatter present.

Dripped BloodDripped Blood

Spilled BloodSpilled Blood

"Projected Blood" (through syringe)"Projected Blood" (through syringe)

PROJECTED BLOODSTAINSPROJECTED BLOODSTAINS

Projected bloodstains are created Projected bloodstains are created when an exposed blood source is when an exposed blood source is subjected to an action or force, subjected to an action or force, greater than the force of gravity. greater than the force of gravity. (Internally or Externally produced)(Internally or Externally produced)

The size, shape, and number of resulting stains will depend, primarily, on the amount of force utilized to strike the blood source.

Arterial Spurt / GushArterial Spurt / GushBloodstain pattern(s) resulting from blood exiting

the body under pressure from a breached artery:

Cast-off StainsCast-off StainsBlood released or thrown from a blood-bearing

object in motion:

Impact SpatterImpact Spatter Blood stain patterns created when a blood source receives

a blow or force resulting in the random dispersion of smaller drops of blood.This category can be further subdivided into;

Low VelocityGravitational pull up to 5 feet/sec. Relatively large stains 4mm in size and greater

Medium VelocityMedium VelocityForce of 5 to 25 feet/sec.

Preponderant stain size 1 to 4mm in size

High VelocityHigh Velocity

Force of 100 feet/sec. and greaterPreponderant stain size 1mm in size & smaller Mist like appearance

DIRECTIONALITY OF DIRECTIONALITY OF BLOODSTAINSBLOODSTAINS

When a droplet of blood strikes a surface perpendicular (90˚) the resulting bloodstain will be circular.That being the length & width of the stain will be equal.

Blood that strikes a surface at an angle less than 90˚ will be elongated or have a tear drop shape.Directionality is usually obvious as the pointed end of the bloodstain ( tail ) will alwayspoint in the direction of travel.

IMPACT ANGLE DETERMINATIONIMPACT ANGLE DETERMINATION

ANGLE of IMPACTANGLE of IMPACT is the acute angle is the acute angle formed between the direction of the formed between the direction of the blood dropblood drop& the plane of the surface it strikes& the plane of the surface it strikes

POINT OF CONVERGENCE AND POINT OF CONVERGENCE AND ORIGIN DETERMINATIONORIGIN DETERMINATION

Principles of HeredityPrinciples of Heredity

The enzymes & proteins that make The enzymes & proteins that make up a person are inherited from their up a person are inherited from their parents in genetically controlled parents in genetically controlled traits. They are permanent feature’s traits. They are permanent feature’s of a persons biological make-up at of a persons biological make-up at the moment of conception.the moment of conception.

Genes & ChromosomesGenes & Chromosomes

Hereditary material is transmitted via Hereditary material is transmitted via microscopic units called genes. (They microscopic units called genes. (They determine the nature & growth of determine the nature & growth of virtually every body structure)virtually every body structure)

Genes are on chromosomes that are in Genes are on chromosomes that are in the nucleus of every body cell. They are the nucleus of every body cell. They are in pairs & each human cell has 46 total, in pairs & each human cell has 46 total, except the egg & sperm which have 23. except the egg & sperm which have 23. (Once combined they are a zygote with (Once combined they are a zygote with 46.)46.)

The genes come in pairs that are called The genes come in pairs that are called alleles and their position on the alleles and their position on the chromosomes is called the locus.chromosomes is called the locus.

An individual’s blood type is determined An individual’s blood type is determined by 3 genes, designated as A-B-O, if it is by 3 genes, designated as A-B-O, if it is made up of 2 of the same alleles it is made up of 2 of the same alleles it is homozygous (AA, BB, OO) if it has 2 homozygous (AA, BB, OO) if it has 2 different it is heterozygous (AB, AO, BO)different it is heterozygous (AB, AO, BO)

Codominant is both heterzygous & equal Codominant is both heterzygous & equal in representative allele strength- ABin representative allele strength- AB

Draw a Punnett square - 4 small squares in the shape Draw a Punnett square - 4 small squares in the shape of a window. Write the possible gene(s) of one parent of a window. Write the possible gene(s) of one parent

across the top and the gene(s) of the other parent across the top and the gene(s) of the other parent

along the side of the Punnett square.along the side of the Punnett square.

Forensic Characterization of SemenForensic Characterization of Semen

Many cases are sexual offenses & require Many cases are sexual offenses & require the examination of exhibits for seminal the examination of exhibits for seminal stains.stains.

2 step process:2 step process: 1. locate stain (an arduous task)1. locate stain (an arduous task) 2. stains must be tested to prove 2. stains must be tested to prove

identity. (it may be tested for blood type identity. (it may be tested for blood type of the individual it originated from or DNA of the individual it originated from or DNA extracted)extracted)

Acid Phosphatase Color TestAcid Phosphatase Color Test

Acid phosphatase is is an enzyme Acid phosphatase is is an enzyme secreted by the prostate gland.secreted by the prostate gland.

It’s presence can be detected when it It’s presence can be detected when it comes into contact with an acidic solution comes into contact with an acidic solution of sodium alpha naphthylphosphate & of sodium alpha naphthylphosphate & Fast blue dye. Fast blue dye.

(you can get it to emit light w/ exposure (you can get it to emit light w/ exposure to 4-methyl umbelliferyl phosphate (MUP) to 4-methyl umbelliferyl phosphate (MUP) ))

Semen Confirmation testSemen Confirmation test

Unequivocally identified by presence Unequivocally identified by presence of spermatoza under a microscope. of spermatoza under a microscope. Usually found by immersing the Usually found by immersing the stained material in a small volume of stained material in a small volume of water, rapidly stirring the liquid, put water, rapidly stirring the liquid, put a drop of water on a slide.a drop of water on a slide.

PSA- prostate specific antigenPSA- prostate specific antigen

Seminal plasma – can be tested for Seminal plasma – can be tested for with electrophoresis.with electrophoresis.

Can also be identified by monoclonal Can also be identified by monoclonal PSA antibody being attached to a dye PSA antibody being attached to a dye & placed on a porous membrane. & placed on a porous membrane.

Collection of Rape EvidenceCollection of Rape Evidence

Rape can be confirmed by the Rape can be confirmed by the presence of seminal fluid, by presence of seminal fluid, by bruising. Bleeding or tearing in the bruising. Bleeding or tearing in the vaginal area. There may be a vaginal area. There may be a transfer of blood, hair semen or transfer of blood, hair semen or fibers in a sexual assault.fibers in a sexual assault.

The evidence must be collected and The evidence must be collected and handled carefully.handled carefully.

CollectionCollection

Items suspected of containing evidence must Items suspected of containing evidence must be collected (like outer and undergarments), be collected (like outer and undergarments), packaged separately, in paper bags. (no packaged separately, in paper bags. (no plastic!)plastic!)

When a victim removed their clothing:When a victim removed their clothing: Lay clean sheet outLay clean sheet out Place white paper on sheetPlace white paper on sheet Undress on top of paper to gather anything that Undress on top of paper to gather anything that

may fall, like hairs or fiber.may fall, like hairs or fiber. Fold the paper & package to send to the labFold the paper & package to send to the lab Collect each piece of clothing separately- avoid Collect each piece of clothing separately- avoid

cross-contaminationcross-contamination

Medical ExamMedical Exam The victim will be medically examined as The victim will be medically examined as

quickly as possible after the assault.quickly as possible after the assault. Rape-collection kit or (SAEK) will be used by Rape-collection kit or (SAEK) will be used by

the medical staff, following is collected:the medical staff, following is collected: Pubic combingsPubic combings Pubic hair/standard reference samplePubic hair/standard reference sample External genital dry-skin areasExternal genital dry-skin areas Vaginal swabs & smearVaginal swabs & smear Cervix swabCervix swab Rectal swab & smearRectal swab & smear Head hairsHead hairs Blood sampleBlood sample Fingernail scrapingsFingernail scrapings All clothingAll clothing Urine specimenUrine specimen

Collected from suspect if arrestedCollected from suspect if arrested

All clothing (believed to be worn in All clothing (believed to be worn in assault)assault)

Pubic hair combingsPubic hair combings Pulled head & pubic hair Pulled head & pubic hair

standard/reference samplesstandard/reference samples Penile swab – if within 24 hours of the Penile swab – if within 24 hours of the

assaultassault A blood sample or buccal swab for DNA A blood sample or buccal swab for DNA

typing purposes.typing purposes.

DNA & RapeDNA & Rape

With the advent of DNA the collection With the advent of DNA the collection may not be as extensive, because so may not be as extensive, because so much information can be gathered much information can be gathered by a DNA sample.by a DNA sample.

What Samples can DNA be What Samples can DNA be collected from?collected from?

Sweaty t-shirts Sweaty t-shirts Undergarments Undergarments Semen stains Semen stains Vaginal stains Vaginal stains Paper or plastic cup Paper or plastic cup Glass Glass Ear wax Ear wax Fingernail clippings Fingernail clippings Socks Socks Urine Urine

Licked stamps Licked stamps (Inner) cheek swabs (Inner) cheek swabs Hair with roots Hair with roots Dried blood Dried blood Whole blood Whole blood Chewed gum Chewed gum Dental floss Dental floss Cigarette butts Cigarette butts Used tissueUsed tissue Dried skin Dried skin Used razorUsed razor