cystic fibrosis (cf) - gene location

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Cystic Fibrosis (CF) - gene location

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Cystic Fibrosis (CF) - gene location. Cystic Fibrosis (CF): Molecular defect. Cystic Fibrosis (CF): One gene may lead to many phenotypic effects. Cystic Fibrosis lungs. Lung from a CF patient, showing extensive destruction as a result of obstruction and infection. Normal lung. - PowerPoint PPT Presentation

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Page 1: Cystic Fibrosis (CF) - gene location

Cystic Fibrosis (CF) - gene location

Page 2: Cystic Fibrosis (CF) - gene location

Cystic Fibrosis (CF): Molecular defect

Page 3: Cystic Fibrosis (CF) - gene location

Cystic Fibrosis (CF): One gene may lead to many phenotypic effects

Page 4: Cystic Fibrosis (CF) - gene location

Cystic Fibrosis lungs

Normal lung Lung from a CF patient, showing extensive destruction as a result of obstruction and infection

Page 5: Cystic Fibrosis (CF) - gene location

Normal pancreasCF Pancreas showing infiltration of fat and fibrotic lesions

Cystic Fibrosis Pancreas

Page 6: Cystic Fibrosis (CF) - gene location
Page 7: Cystic Fibrosis (CF) - gene location

Tay Sachs

• Defective enzyme that breaks down a particular fatty substance

Page 8: Cystic Fibrosis (CF) - gene location
Page 9: Cystic Fibrosis (CF) - gene location

ALPHA GLOBIN ALPHA GLOBIN

BETA GLOBIN BETA GLOBIN

Sickle cell mutation

Heme

Iron atom

Heme

Iron atom

Sickle cell mutation

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The hemoglobin tetramer

Page 10: Cystic Fibrosis (CF) - gene location

Normal and Sickled Cell

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Page 11: Cystic Fibrosis (CF) - gene location

Sickle Cell Anemia (AR)

Aggregation of hemoglobin molecules. Mutant hemoglobin molecules in red cells stack to form rodlike structures, which causes the red cells to deform.

Page 12: Cystic Fibrosis (CF) - gene location

The Genetics of Cancer

Page 13: Cystic Fibrosis (CF) - gene location

Fig. 11-12Signaling cell

DNA

Nucleus

Transcriptionfactor(activated)

Signaling molecule Plasma

membraneReceptorprotein

Relayproteins

TranscriptionmRNANewprotein

Translation

Target cell

2

1

3

4

5

6

Signal Transduction:

How a cell can respond to signals from its environment

Results in a change in which genes are expressed (turned on)

Page 14: Cystic Fibrosis (CF) - gene location

Fig. 11-20aGrowth factor

Protein thatStimulatescell division

Translation

Nucleus

DNA

Target cell

Normal productof ras gene

Receptor

Relayproteins

Transcriptionfactor(activated)

Hyperactiverelay protein(product ofras oncogene)issues signalson its own

Transcription

Ras is an oncogene (cancer gene) the normal form of the gene is called a proto-oncogene

Oncogenes STIMULATE cell division

Page 15: Cystic Fibrosis (CF) - gene location

Fig. 11-18a

Mutation withinthe gene

Hyperactivegrowth-stimulatingprotein in normalamount

Proto-oncogene DNA

Multiple copiesof the gene

Gene moved tonew DNA locus,

under new controls

Oncogene New promoter

Normal growth-stimulatingprotein in excess

Normal growth-stimulatingprotein in excess

Page 16: Cystic Fibrosis (CF) - gene location

Fig. 11-20bGrowth-inhibiting factor

Protein thatinhibitscell division

Translation

Normal productof p53 gene

Receptor

Relayproteins

Transcriptionfactor(activated)

Nonfunctional transcriptionfactor (product of faulty p53tumor-suppressor gene) cannot trigger transcription

Transcription

Protein absent(cell divisionnot inhibited)

Normal tumor-suppressor genes prohibit cell division

Page 17: Cystic Fibrosis (CF) - gene location

Fig. 11-18b

Mutated tumor-suppressor geneTumor-suppressor gene

Defective,nonfunctioningprotein

Normalgrowth-inhibitingprotein

Cell divisionunder control

Cell division notunder control

Page 18: Cystic Fibrosis (CF) - gene location

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Page 19: Cystic Fibrosis (CF) - gene location
Page 20: Cystic Fibrosis (CF) - gene location

Both alleles of BRCA1 or both alleles of BRCA2 must be mutant for cancer to develop.

Why would in follow a dominant inheritance pattern?

A tissue comprised of billions of cells heterozygous for BRCA1 or BRCA2

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