how to read a pedigree

8/19/2019 How to Read a Pedigree

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Pedigree ChartsPedigree ChartsThe family tree of geneticsThe family tree of genetics


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Pedigree ChartsPedigree Charts

I

II

III


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OverviewOverview

I.I. What is a pedigree?What is a pedigree?

a.a. DefinitionDefinition

b.b. UsesUses

II.II. Constructing a pedigreeConstructing a pedigree

a.a. SymbolsSymbols

b.b. Connecting the symbolsConnecting the symbols

III.III. Interpreting a pedigreeInterpreting a pedigree


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Constructing a PedigreeConstructing a Pedigree

MaleMale

FemaleFemale


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Connecting Pedigree SymbolsConnecting Pedigree Symbols

Fraternal twinsFraternal twins

Identical twinsIdentical twins

Examples of connected symbols:Examples of connected symbols:


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nterpreting a Pedigree Chartnterpreting a Pedigree Chart

&.&. %etermine if the pedigree chart shows an%etermine if the pedigree chart shows an

autosomal or #$linked disease.autosomal or #$linked disease.

' If most of the males in the pedigree areIf most of the males in the pedigree are

affected the disorder is #$linkedaffected the disorder is #$linked

' If it is a ()*() ratio between men andIf it is a ()*() ratio between men and

women the disorder is autosomal.women the disorder is autosomal.


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!nswer !nswer

AutosomalAutosomal


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nterpreting a Pedigree Chartnterpreting a Pedigree Chart

+.+. %etermine whether the disorder is%etermine whether the disorder isdominant or recessive.dominant or recessive.

' If the disorder is dominant, one ofIf the disorder is dominant, one of

the parents must have the disorder.the parents must have the disorder.

' If the disorder is recessive, neitherIf the disorder is recessive, neither

parent has to have the disorderparent has to have the disorder

because they can be heterozygous.because they can be heterozygous.


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Example of Pedigree ChartsExample of Pedigree Charts

%ominant or -ecessive"%ominant or -ecessive"


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!nswer !nswer

%ominant%ominant


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Example of Pedigree ChartsExample of Pedigree Charts

%ominant or -ecessive"%ominant or -ecessive"


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!nswer !nswer

-ecessive-ecessive


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SummarySummary

edigrees are family trees that e/plainedigrees are family trees that e/plain

your genetic history.your genetic history.

edigrees are used to find out theedigrees are used to find out the

probability of a child having a disorderprobability of a child having a disorder

in a particular family.in a particular family.

To begin to interpret a pedigree,To begin to interpret a pedigree,

determine if the disease or condition isdetermine if the disease or condition isautosomal or #$linked and dominant orautosomal or #$linked and dominant or

recessive.recessive.


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Pedigree Chart "Cystic #ibrosisPedigree Chart "Cystic #ibrosis


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&aryotype&aryotype


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Chromosome Number Chromosome Number

%ifferent 0 for%ifferent 0 fordifferent speciesdifferent species

Full setFull set 11

+21+21DiploidDiploid

N=N= pairs pairs & pair from mother& pair from mother

& pair from father& pair from father

3umans13umans1 !" pairs!" pairs oror

45 total45 total

HomologousChromosomes

are the sets of

each pair


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!utosomes ' Sex !utosomes ' Sex

ChromosomesChromosomesAutosomes = # 1-

22 for all traitsexcept sex

Sex chromosomes=Pair # 23 XX(female) or

XY(male)


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(own Syndrome) * of +,-(own Syndrome) * of +,-


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&linefelter &linefelter .s ) //0.s ) //0


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1utation1utation ChangeChange in DN+in DN+codecode Caused by&Caused by&

.. ChemicalChemical

damagedamage

!.!.

$rrors in$rrors in/eplication/eplication

".". 01ray damage01ray damage

2.2. U3 damageU3 damage

A

T

GC

Ato A

G C


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1utation1utationChanges in theChanges in the

DN+ codeDN+ code= Changes in= Changes in

the finalthe finalproteins madeproteins made

=Changes in=Changes inthe organismthe organism


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-3 2ransgenic tobacco plant?-3 2ransgenic tobacco plant?

4enetically4enetically

engineeredengineered

Inserting fireInserting firefly genes intofly genes into

the plantthe plant

UsingUsing 5cut 65cut 6paste7paste7

en8ymesen8ymes


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4ecombinant (5!:4ecombinant (5!:

55/ecombine7/ecombine7

Connecting orConnecting orreconnecting DN+reconnecting DN+

fragmentsfragments

DN+ of t9o differentDN+ of t9o different

organismsorganisms 9/ample: lab of inserting human %2A into9/ample: lab of inserting human %2A into

bacteriabacteria

% ti E i i f li% ti E i i f li


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%enetic Engineering of nsulin%enetic Engineering of nsulin

Human DNA cut out

Human DNA put

into bacteria DNA

Bacteria DNA is opened upMany Bacteria

Grow human

insulin


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63 2ransgenic Organism:63 2ransgenic Organism:

55trans7 = acrosstrans7 = across

55genic7 = racegenic7 = raceContains genes fromContains genes from

another organismanother organism'acteria'acteria3irus3irus

:uman:uman


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73 2obacco 4ecombinant (5!73 2obacco 4ecombinant (5!

Process:Process:

a.a. Isolated %2A to beIsolated %2A to be

inserted into hostinserted into host

b.b. Attach %2A fragment to aAttach %2A fragment to avehicle ;vector


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4estriction En8ymes:4estriction En8ymes:

Restriction Enzymes cut DNA at

very specific sites

Separate the base pairs of bothstrands

“Scissors” in Recombinant DNA

Human CutBacterium

DNA cut


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9393 Stic;y ends


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=ectors ) vehicles=ectors ) vehiclesCarry foreign DN+Carry foreign DN+fragments into the hostfragments into the host

7acteria carried the firefly7acteria carried the firefly%2A into the tobacco cells%2A into the tobacco cells

'iological or'iological or

#echanical#echanical


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=ectors:=ectors:

'iological&'iological&3irus3irus'acterial'acterialplasmidplasmid

;circular;circularDN+


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4ecombinant (5! >ses:4ecombinant (5! >ses: =row human=row human

hormones inhormones inbacteria culturesbacteria cultures

ArtificialArtificial

sweeteners usingsweeteners using

bacteria to makebacteria to make

amino acidsamino acids

Study humanStudy human

diseases bydiseases byinserting humaninserting human

%2A into mice%2A into mice

-eplace incorrect-eplace incorrect

%2A%2A

/eplace harmful/eplace harmful

bacteria on plantsbacteria on plants Nitrogen bacteriaNitrogen bacteria

in the soil 6in the soil 6

plants to maeplants to mae

fertili8erfertili8er Impro>e transportImpro>e transport

of fruitsof fruits

/esist diseases/esist diseases

Increase proteinIncrease protein

productionproduction

how to read a pedigree

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