Genetic Disease Flashcards
What are the signs and symptoms of CF?
- Sinus problems
- Nose polyps
- Excessive mucus
- Breathing problems
- Frequent lung problems
- Enlarged heart
What are the significant genetic aspects of CF
- Autosomal recessive
- Caused by faulty 7q31 gene
What does the 7q31 gene code for?
Chlorine channels in cells
What does normal function of the protein that 7q31 codes for result in?
Ability to move chloride ions out of the cell
What happens when the 7q31 gene is faulty?
Inability to move chloride ions out of the cell
What does this defective channel result in?
Sticky mucus accumulates on the outside of the cell
What neuromuscular disorders can be caused by mutations in genes?
- Myotonic dystrophy
- DMD
What is myotonic dystrophy an example of
- Anticipation inheritance (age of onset decreases with next gen)
- Non mendelian inheritance
- Autosomal dominant disorder
What does myotonic dystrophy cause?
- Distal muscle weakness
- Learning disabilities
Where does this distal muscle weakness present?
- Face
- Hands
- Lower legs
What is DMD an example of
- X linked recessive
What gene mutates to cause DMD?
Dystrophin
What does DMD cause in early life?
- Weakness of proximal muscles close to axial body
- Delay in walking if any at all
When does DMD usually cause mortality?
Roughly 20 but has improved significantly in recent years
In what cells do mutations lead to inheritable disposition to cancer?
Germline cells
What two genes can lead to inherited cancer?
- Proto oncogenes
- Tumour suppressor genes
What do mutations on proto oncogenes cause?
They turn into oncogenes
What do proto oncogenes usually do?
Code for cell growth and regulation
What do oncogenes fail to do?
Regulate growth
What do oncogenes cause with the rate of growth?
They speed it up
What does the speed up of growth and disregulation of cells by oncogenes result in
Tumour formation
How many mutations on a proto oncogene can lead to cancer?
1
What are the normal jobs of tumour suppressor genes
Act as the brakes on the cell cycle
What can tumour suppressor genes cause a cell to do if it is damaged?
Apoptosis
How many copies of the tumour suppressor gene are there?
2
If mutations happen in both tumour suppressor genes what happens?
Cancer will arise
If one of these mutations occurs in the germline cell, what is the child designated as
A carrier
