What is What is genetics?genetics?

HEREDITYHEREDITYThe study of...The study of...

What is HEREDITY?

The passing of traits from parent The passing of traits from parent to offspring. to offspring.

Why do we care about genetics?

• Genetics has determined the history and will determine the

future of all living things.

• We are in the “Age of Genetics”

Chromosomes, Genes, Traits and Alleles

Chromosomes are strands Chromosomes are strands ofof

______that carry our ______that carry our

__________ __________ __________ __________

Chromosomes• Chromosomes are

made up of many GENES.

• Genes are

instructions for

the TRAITS

you have.

VISUALIZE the GENESEACH X is a EACH X is a chromosome.chromosome.

On the X are little On the X are little marks. Each marks. Each

mark is a gene.mark is a gene.

Where are they? Where are they? IN THE NUCLEUSIN THE NUCLEUS

TEST YOURSELF

1. DNA is held in what part of the cell?1. DNA is held in what part of the cell?

2. DNA is grouped into sets of what in each cell?2. DNA is grouped into sets of what in each cell?

FACT: These 23 sets of chromosomes are called your FACT: These 23 sets of chromosomes are called your genome!genome!

3. Each chromosome contains DNA grouped into something called 3. Each chromosome contains DNA grouped into something called _________ which carries information that tells the cell to make _________ which carries information that tells the cell to make a unique protein that will perform a special function.a unique protein that will perform a special function.

• Genes are instructions for the ___________ you have. Genes are instructions for the ___________ you have.

In your note packet, write down examples of some human traits.

• Example: Eye color is a human trait

Homologous chromosomes, alleles and more

Remember what homologous chromosomes are?

THEY ARE: THEY ARE: A pair of chromosomes containing the same gene sequences, each derived from one parent. The chromosomes

tend to pair during meiosis.

Homologous Chromosomes

Each homologous chromosome has the same traits on it, but they can be for different alleles.

• WHAT IN THE WORLD IS AN ALLELE?

ALLELE

•Possible options for one traitPossible options for one trait

EXAMPLE: brown eye color or blue eye colorEXAMPLE: brown eye color or blue eye color

Using the list of human traits you have already made in your notes, list possible alleles for the traits.

• Example: The trait is eye color– Possible alleles are brown and blue

The homologous chromosomes below have the same traits on them, but they are for two

different alleles.

Both chromosomes in the homologous pair containthe trait for hair texture, but one carries the allele for curly hair & the other one carries the allele for

straight hair.

                       

             

GENE INTERACTION….

• What the organism looks like.

• The actual genes (alleles) the organism has.

•We use big andsmall letters to symbolize genes

When figuring out what the PHENOTYPE will be when a

certain GENOTYPE is present, you need to find out the

_____________ of each allele.

How do alleles interact with each

other?

3 Gene Interactions

• Dominant vs. Recessive

• Incomplete Dominance

• Codominance

Dominant vs. Recessive

Dominant/Recessive interactions

• The dominant allele will “cover up” the recessive allele.

Incomplete Dominance interactions

When the 2 different alleles are present, the phenotype will look like a BLENDING of the two.

INCOMPLETE DOMINANCE

A trick to remember this is “A trick to remember this is “ININ” ” your “your “blenderblender” we make a shake.” we make a shake.

‘‘IN’COMPLETE=‘BLENDING’IN’COMPLETE=‘BLENDING’

Codominance• Both alleles act as dominant, so

you will get a result with both alleles shown fully.

CODOMINANCE REMEMBERED:

CO- BOTHCO- BOTH

Think of Co-ed (means BOTH boys and girls)Think of Co-ed (means BOTH boys and girls)

Codominance means BOTH traits showCodominance means BOTH traits show

Gene interaction questions(These genes are not actually real, they are for example only)

• A girl inherits a long eyelash gene from her father and a short eyelash gene from her mother. The short eyelash gene is dominant and the long eyelash gene is recessive.

What is the length of the girl’s eyelashes?

Her eyelashes are short

Gene interaction questions(These genes are not actually real, they are for example only)

• The interaction of genes for height of the Scar Barked Fast Sapping Evergreen Tree show incomplete dominance.

A tall tree is crossed with a short tree, what will the height of the new tree be?

Medium height

Gene interaction questions(These genes are not actually real, they are for example only)

• The interaction of genes for height of the Scar Barked Fast Sapping Evergreen Tree show incomplete dominance.

Another question, a short tree is crossed with another short tree, what will the height of the new tree be?

Short height

Gene interaction questions(These genes are not actually real, they are for example only)

• The genes for fur design of Patagonia Panthers are codominant. The 2 possible designs for fur are spotted and striped.

A spotted panther is mated with a striped panther. What will the fur design of the baby panther be?

Spotted with stripes

Heredity and Genotype

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Look at these cells• Which is haploid? • Which is diploid?• Which is a body cell? Which is a sperm or egg cell?

In each of your body cells, how many genes do you have for 1

specific trait?

2Why?There is one gene on each of the homologous pairs. You got one gene from your mom and one gene from your dad.

Since egg and sperm cells are haploid, how many genes do you have for each trait

in an egg?

In a sperm?

• The egg and sperm both have one gene for each trait.

• The homologous pairs were separated during meiosis.

1111

Remember:Meiosis only occurs in Meiosis only occurs in __________________.__________________.SEX CELLSSEX CELLS

SEXSEX

The homologous pairs were separated during meiosis.

How and when are homologous pairs separated in meiosis in order to make a sperm or an

egg?

Metaphase I: How are the homologous chromosomes lined up?

In metaphase I In metaphase I

of meiosis,of meiosis,

homologous pairs are homologous pairs are

lined up so thelined up so the

homologous pairs homologous pairs

are next are next

to one another.to one another.

Anaphase I: How are homologous

chromosomes separated?Homologous Homologous

pairs are pairs are separated in separated in Anaphase I Anaphase I of meiosis.of meiosis.

At the end of meiosis I, the homologous chromosomes have been separated, the cells are now

haploid.

The homologous pairs are split up randomly, so we don’t know which particular chromosome of each pair will be

found in each cell.

Law of Independent Assortment

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The alleles for a trait separate when gametes are formed. These allele pairs are then randomly united at fertilization.

Review Quiz…

Where did you get each of your chromosomes?

• Half from your mother

• Half from your father

How many genes for each trait do you have in each BODY cell?

•2 genes

How many genes for each trait do you have in each SPERM cell?

1 Gene for each traitWHY?

Sperm are haploid

How many genes for each trait do you have in an EGG cell?

1 Gene for each traitBecause eggs are haploid

When a sperm fertilizes an egg, how many genes for each trait

will the baby have?

It has two genes for each trait. The baby will be diploid

Karyotype: All of an organism’s chromosomes are lined up with homologous

pairs being placed next to one another.

Chromosomes Chromosomes #23 are sex cells.#23 are sex cells.

A Bit ‘O’ Genetic History...

THE STUDY OF GENETICS

The Father of Genetics

Gregor Mendel and His Peas

Mendel and His PeasHe used pea plants because:He used pea plants because:

1)1) Unlike animals, they could not Unlike animals, they could not movemove

2)2) Easier to test MANY plants Easier to test MANY plants whereas animals sometimes whereas animals sometimes

take up more space and take up more space and require more maintenancerequire more maintenance

What else….What else….

Why did he use pea Why did he use pea plants and not plants and not

animals? Discuss…animals? Discuss…

What are 5 traits he was looking at and what were the 2 possible alleles for each?

When the gene interaction is dominant vs. recessive, you need

to know the genotypes of the parents in order to accurately

figure out what the possibilities are for their children.

Remember….

• PHENOTYPE = What the organism looks like.

• GENOTYPE = The genes (alleles) the organism has.

Example: A species of bird has 2 possible alleles for wing color, red and green.

The alleles have a dominant vs. recessive interaction with one another.

The red allele is dominant over the green allele.

We will be representing the red allele as “R” and thegreen allele as “r”.

Red allele (R) is dominant over Green allele (r)• A bird has a red wing, what are the possible

genotypes for red wing?

The bird could have the genoytpe “R R”or “Rr”

• In genetics, there is a special term to describe both of these combinations.

If the 2 alleles are the same (RR) or (rr) they aresaid to be homozygous. “Homo” means “same”

If the 2 alleles are different (Rr) they are called heterozygous. “Hetero” means “different”

• Lemurs have 2 possible alleles for tail appearance, fluffy and straight.

• Fluffy (F) is dominant over straight (f).

The phenotype of lemur #1 is fluffy tailThe phenotype of lemur #2 is straight tail

• What are the possible genotypes for lemur #1?• What are the possible genotypes for lemur #2?

Lemur #1: FF (homozygous) or Ff (heterozygous)Lemur #2: ff (homozygous)

Quiz yourself

A man inherited from his mother, a chromosome which has the blue eye color allele on it. He also inherited from his father, the chromosome which has

the brown eye color allele on it.

• The man has a child, which eye color allele will the child inherit, blue or brown?

Answer: It is impossible to tell, it could be eitherthe Brown or the blue.

What is his genotype? Bb - heterozygous

Did you get Did you get those? those?

You are smart!You are smart!

Predicting possible outcomes

• Punnet squares– Possibilities for

genetic combinations

Punnet square problem #1A man who is heterozygous for brown eyes has a baby with a woman who is heterozygous for brown eyes.

What are the possible phenotypes and genotypestheir children could have? Do a Punnet square

The brown eye allele is dominant over blue.

1. Brown is dominant over blue2. Both parent’s phenotypes are brown.3. Both parents are heterozygous - Bb

Punnet SquareMother’s and father’s genotypes are both BbPossible egg genes are B or bPossible sperm genes are B or b

B b

B bPossible genotypes for offspringare:

BB

Bb

Bb

bb

BB, Bb, bbPossible phenotypes are:Brown and blueWhat are the chances of Getting a brown eyed child? A blue eyed child?The ratio is 3:1 brown to blue. 75% chance of brown and 25% chance of blue

Punnet SquareMother’s and father’s genotypes are both BbPossible egg genes are B or bPossible sperm genes are B or b

B

b

B bPossible genotypes for offspringare:

BB

Bb

Bb

bb

BB, Bb, bbPossible phenotypes are:Brown and blueWhat are the genotypic ratios?

The ratio is 1:2:11 BB 2 Bb 1 bb

brown and yellow 2:2 --> 1:1

Punnet Square Question #2A female duck with yellow feet mates with a maleduck who is heterozygous for brown feet. What are the possible feet colors for the chicks?Brown is dominant over yellow.Mother duck’s genotype is: bb

Father duck’s genotype is: Bb

b

b

B b

Bb bb

Bb bb

Possible phenotypes are:

Possible genotypes are:Bb and bb 2:2 --> 1:1

Going further….

Do some Do some examples in examples in

the class notesthe class notes

Punnet Squares With 2 Traits

Mother’s genotype:Bbll

Father’s genotype:bbLl

A woman who is heterozygous for brown eyes and has small toes marries a man who has blueeyes and heterozygous for large toes. What are the possible genotypes and phenotypes oftheir children?

Brown eyes are dominant over blueLarge toes are dominant over small toes

To form the possible egg and sperm…

Think:Think:

First with third, first with fourthFirst with third, first with fourth

Second with third, second with fourthSecond with third, second with fourthBbll

BlBl BlBl blbl blbl

Punnet Squares With 2 TraitsMother’s genotype: B b l l Father’s genotype: b b L l

Possible eggs: Bl, Bl, bl, bl

Possible sperm:bL, bl, bL, bl

Bl

Bl

bl

bl

bL bl bL bl

BbLl BbLlBbll Bbll

BbLl BbLlBbll Bbll

bbLl bbLlbbll bbll

bbLl bbLlbbll bbll

Punnet Squares With 2 TraitsMother’s genotype: B b l l Father’s genotype: b b L l

Bl

Bl

bl

bl

bL bl bL bl

BbLl BbLlBbll Bbll

BbLl BbLlBbll Bbll

bbLl bbLlbbll bbll

bbLl bbLlbbll bbll

Possible genotypes:BbLl BbllbbLl bbll1:1:1:1 Ratio

Possible phenotypes:

Brown eyes/large toes

Brown eyes/small toes

blue eyes/large toes

blue eyes/small toes

1:1:1:1 Ratio

Punnet Squares 2 Traits - DifficultA female wavy fur spaniel with heterozygous brown

paws is mated with a male wavy fur spaniel with heterozygous brown paws.

•What are the possible genotypes and ratios? •What are the possible phenotypes and ratios?

Straight and curly fur show incomplete dominance.Brown paws are dominant over white paws.

Female’s genotype is:Male’s genotype is: csBb

csBb

Punnet Squares 2 Traits - DifficultFemale’s genotype is: csBb Male’s genotype is: csBb

Possible genes in eggs: cB, cb, sB, sbPossible genes in sperm: cB, cb, sB, sb

cB

cb

sB

sb

cB cb sB sb

ccBB ccBb csBB csBb

ccBb ccbb csBb csbb

csBB csBb ssBB ssBb

csBb csbb ssBb ssbb

Punnet Squares 2 Traits, #2Genotypes:

cB

cb

sB

sb

cB cb sB sb

ccBb csBB csBb

ccBb ccbb csBb csbb

csBB csBb ssBB ssBb

csBb csbb ssBb ssbb

ccBB ccBb csBB csBb ccbbcsbb ssBB ssBb ssbb

csBB 2csBb 4ccbb 1csbb 2ssBB 1ssBb 2ssbb 1

ccBB 1ccBb 2

Genotype ratio:

ccBB

1:2:2:4:1:2:1:2:1

Punnet Squares 2 Traits, #2Genotypes: CCBB CCBb CSBB CSBb CCbb

CSbb SSBB SSBb SSbb

CSBB 2CSBb 4CCbb 1CSbb 2SSBB 1SSBb 2SSbb 1

CCBB 1CCBb 2

Genotype ratio: Phenotype ratio:Curly/Brown 3Wavy/Brown 6Curly/white 1Wavy/white 2Straight/Brown 3Straight/white 1

3 : 6 : 1 : 2 : 3 : 1

Sometimes genes change by accident.

It is call a…

MutationsOOPS!OOPS!

There are 3 possible outcomes

when a mutation occurs...

1. LethalIt kills the organism before birth or later.

2. Negative Effect

Ranging from minor severe None at all

3. Positive Effect Very rarely happens this way

Makes organism better adapted

2 examples are…

• A mutation occurred, and actually helped these organism survive!

•Advantage increases an animal's chances of survival.

•Chances of reproducing and passing on the trait.

Example #1: Camouflage

•Mutation that happened in malaria-prone regions.

•More likely to survive malaria epidemics.

•They survived when others did not, this allowed the trait to be passed down through generations.

Example #2: Sickle Cell Anemia

Types of Mutations

Type A:Mutations that occur during

Meiosis

Type B:Mutations that occur during

DNA replication

Type A:Mutations That Occur

During Meiosis

Mutations That Occur During Meiosis

Examples:Examples:

Duplication MutationDuplication Mutation

Deletion MutationDeletion Mutation

Inversion MutationInversion Mutation

TranslocationTranslocation

NondisjunctionNondisjunction

Type A:Mutations That Occur During Meiosis

During Prophase Crossing over done incorrectly

Type A:Mutations That Occur During Meiosis

During Anaphase II Chromatids separating incorrectly

2424 23

4747

Type B:POINT MUTATIONS

Mutations that occur during

DNA replication.

Mutations that arise from nucleotide

bases having errors are called

POINT MUTATIONSPOINT MUTATIONS

POINT MUTATIONS ARE

Base Pair AdditionBase Pair Addition

Base Pair DeletionBase Pair Deletion

Base Pair SubstitutionBase Pair Substitution

Let’s see if you can figure it out!Activity

Fill in your pages

What causes mutations?

MUTATION CAUSES1.1. Natural Causes- mistakes in the DNANatural Causes- mistakes in the DNA

•IN THE IN THE CLEANING SUPPLIESCLEANING SUPPLIES YOU USE YOU USE

•IN THE IN THE TOBACCOTOBACCO THAT PEOPLE USE THAT PEOPLE USE

2. Environmental Factors…Mutagens2. Environmental Factors…Mutagens

•IN THE IN THE FOOD FOOD YOU YOU EATEAT

3. UV-Rays & X-Rays3. UV-Rays & X-Rays

How many people do you know who smoke?

1 out of every 3 tobacco users will die from a tobacco

related illness.

Think for a second and count them.

TobaccoTobaccoStinksSucksSmellsAnd KILLS

In the dentist’s office, why do they place a lead apron over a person’s lap?

They want to protect the reproductive organs. If a mutation occurs in the reproductive organs, it may end up disfiguring a future child, or worse.

4. Heavy Metals

• Lead • Mercury• Cadmium• (Not heavy

metal like Metallica)

MUTATION CAUSES CONT…

5. UV Raysa. Holes in the ozone

layerb. Tanning beds

6. Nuclear radiation

Things that cause mutations are called

Mutagens

Exposure to mutagens can cause mutations in 2

general areas.1. Mutations in the sex cells, eggs and sperm.What do you think these mutations might lead to?

2. Mutations in the other cells of the body. What do you think these might lead to?

BIRTH DEFECTS OR DEATHBIRTH DEFECTS OR DEATH

CANCERCANCER

If you do not mind…

•Please stand up if you or someone in your Please stand up if you or someone in your immediate family has had cancer.immediate family has had cancer.

•Please stand up if someone you are related Please stand up if someone you are related to has had cancer.to has had cancer.

•Please stand up if you know someone Please stand up if you know someone personally who has had cancer.personally who has had cancer.

•Please stand up if you have a friend who is Please stand up if you have a friend who is related to someone who has had cancer.related to someone who has had cancer.

So what exactly is this ugly disease?

Cancer is a disease where cellsCancer is a disease where cellsbegin to divide by mitosis begin to divide by mitosis

uncontrollably.uncontrollably.

A mutation(s) can occur in one single cell, and by the process of mitosis it can grow into tens of thousands or more cells in a relatively short period of time.

What forms when a cell has What forms when a cell has undergone mitosis uncontrollably undergone mitosis uncontrollably

for a while in one central spot?for a while in one central spot?

A Tumor

Cancer Treatments

1. Surgerical removal of cancer1. Surgerical removal of cancer

2. Chemotherapy- Treatment with 2. Chemotherapy- Treatment with drugs that kill cancer cells or make drugs that kill cancer cells or make

them less active.them less active.

3. Radiation- 3. Radiation- uses high-energy uses high-energy waves, such as X-rays (invisible waves, such as X-rays (invisible

waves that can pass through most waves that can pass through most parts of the body), to damage and parts of the body), to damage and

destroy cancer cells.destroy cancer cells.

4. Another option is a STEM CELL 4. Another option is a STEM CELL TRANPLANTTRANPLANT

Radiation and anti-cancer drugs are very good at destroying

cancer cells, but unfortunately they also destroy healthy cells.

http://www.leapingmedia.com/Media/TransplantAnimation.movhttp://www.leapingmedia.com/Media/TransplantAnimation.mov

THE HUMAN SYSTEM

• 44 “regular” chromosomes, called autosomes

• 2 sex chromosomes (23rd Pair)–X–YTHAT MEANS HUMANS HAVE A TOTAL OF ____

CHROMOSOMES!

What can you tell me about this person by looking at their karyotype?

• He is Male

MALES are MALES are XYXY

What can you tell me about this person by looking at their karyotype?

• She is female

Females are Females are XXXX

What about this person?

Nondisjunction. Heis trisomy for the sex

chromosomes.

• Male with Klinefelter Syndrome.

• What kind of mutation caused this?

What about this person?

Nondisjunction. Sheis monosomy for the X sex chromosome.

• Female with Turner Syndrome.

• What kind of mutation caused this?

Sex linked genesThe X and Y chromosomes do not carry the same genes on

them.

• In fact, the Y chromosome does not carry many useful genes at all.

• When deciding what traits a person carries on their sex chromosomes, it is often useful to consider males as if they are actually missing a chromosome because there are very few useful genes located on the Y chromosome. (Sorry Guys)

Sex Linked GenesWhen we refer to a “sex linked gene”, it meansthat the gene is located on a sex chromosome.

Very few traits are found on the Y chromosome, so when we talk about sex linked genes, you can assume the gene is located on the X chromosome.

Sex Linked Punnet SquaresWhen doing Punnet squares with sex linkedgenes, you have to include the sex chromosomeas well as the gene it carries.

To show that an X chromosome carries a gene,you put the letter as a superscript of the X.

XBXb would indicate a female who isheterozygous for the trait “B”

Color blindness is an X linked gene

A woman who is a carrier (heterozygous) of thecolor blind gene has children with a man who isnot colorblind.

Colorblind (c) is a recessive gene to the dominant color seeing gene (C).

What are the chances that they could have a sonwho is colorblind? A daughter who is color blind?

Genotype of the mother is:

Genotype of the father is:

XCXc

XCY

Possible genotype for the egg:

Possible genotype for sperm:

Color blindness is an X linked geneGenotype of the mother is:

Genotype of the father is:

XCXc

XCY

XC or Y

XC

XC

Xc

YXC or Xc

Possible genotype for the egg:Possible genotype for sperm:

Color blindness is an X linked gene

XC or Y

XC

XC

Xc

Y

XC or Xc

XC XC XC Y

YXcXC Xc

The chance that they willhave a colorblind SON is 50%

The chance that they willhave a colorblind DAUGHTER is 0%(but 50% for a carrier)

Color blindness is an X linked geneA woman who is homozygous for color seeing has a childwith a man who is colorblind. What are the chances that his daughter will be colorblind?What are the chances that his son will be colorblind?

Colorblind (c) is a recessive gene to the dominantcolor seeing gene (C).

Woman’s genotype:

Man’s genotype:

XC XC

Xc Y

There is 0% chance thatthey will have a colorblind boy or girl.

But 100% chanceThat their daughterswould all be carriers.

Color blindness is an X linked geneWoman’s genotype:

Man’s genotype:

XC XC

Xc Y

XC

Xc

XC

Y

XC Xc XC Y

YXcXC XC

Color Blindness Test

What number do you see?Okay, so this is the one that everyone is

supposed to be able to see!

Red/Green Color Blindness Test

What number do you see?

7

Red/Green Color Blindness Test

What number do you see?

2

Male patterned baldness is X linked

One of the science teachers above has 2 children,a boy and a girl. His wife is heterozygous for the male patterned baldness gene. What are the possibilities that his son or daughter will have male patterned baldness?(Male patterned baldness is a recessive allele)

Results

XH

Xh

Xh

Y

H = Hair h = bald

XH XH

Xh Xh

Xh

Xh

Y

Y

50% chance son will bald50% chance daughter could baldTestosterone is needed to “turn on” this balding gene,so it is very unlikely that agirl will go bald even if she is homozygous for this balding gene.

If a young man wants to get some idea if he may have male

patterned baldness, who should he look at, his father

or his mother’s father? Why?

Because the male patterned baldness is sex linked, he did not receive the gene from his father, he got it from his mother. Looking at the father’s side of the family is useless because he got his Y chromosome from his

dad, not an X.

PedigreePedigrees are symbolic representations of a familyand the alleles they have.

When creating a pedigree, this symbol means the person is male.

When creating a pedigree, this symbol means the person is female.

When creating a pedigree, this symbol means the person is of unknown gender. This is oftenused if in the history of family, a child died at birth and the gender of the child is not known.

PedigreeThe horizontal line connecting this man and woman means that they are married.

The same symbol as above but having a diagonal line through the marriage linemeans that the couple is divorced.

This collection of symbols means that the man is divorced and remarried.

A symbol with a diagonal line through it means thatThe person is no longer living.

Pedigree

What collection of symbols could show a couple who is married and has son and a daughter.

Pedigree

A couple is married, they haveA son and a daughter. Their son is married and he and his wife have a son.

Get the idea?

PedigreeRepresenting genetic traits within a pedigree.

The symbol colored in means that the person is homozygous for the allele.

The symbol half colored in means that the person is heterozygous for the allele.

The symbol not colored in means that the person does not have the allele.

Pedigree for the blue eye alleleA pedigree for a brown eye allele

The brown eye allele is dominant

In this family,who has brown eyes?

Everyone except This woman.

Quiz Time

YOU

Who is this? Sister

Quiz Time

YOU

Who is this? Maternalgrandfather

Quiz Time

YOU

Who is this? half sister

Quiz Time

YOU

What information do weknow about your grandmother?

She haspassed away

Quiz Time

YOU

Who is this? Aunt

Quiz Time

YOU

Pedigree for the big nose allele, it is recessive.

Who has a big nose?You and your aunt

Quiz Time

YOU

Pedigree for the big nose allele, it is recessive.

What is the genotype ofyour cousin?

Quiz Time

YOU

Pedigree for the big nose allele, it is recessive.

What is the genotype ofyour cousin? Heterozygous

Paternity tests

• It is possible to tell if a certain man is the father of a baby by comparing the baby’s DNA to his and the baby’s mother.

• Since the DNA the baby has came from it’s mother and father, the DNA should all be accounted for between the 2 parents.

Paternity Test - Match the DNA

Paternity Test - Match the DNA

Paternity Test - Match the DNA

DNA fingerprinting• DNA fingerprinting is quite similar to a paternity

test, but the person’s DNA is compared to DNA found at the crime scene. If the chromosome fragments line up, it positively IDs the person as being part of the crime.