Cystic Fibrosis, Dystrophinopathies and Huntington's Disease Flashcards
(19 cards)
What is a major symptom of Cystic Fibrosis?
Thick and sticky mucus in airways leading to chronic infections and lung damage
This mucus can trap bacteria, leading to serious health complications.
What can Cystic Fibrosis block in the digestive system?
Ducts, resulting in poor digestion of food and potential malnutrition
This blockage prevents enzymes from reaching the gut.
What gene is associated with Cystic Fibrosis?
CFTR gene
CFTR stands for Cystic Fibrosis Transmembrane conductance Regulator.
What does the CFTR protein control?
The flow of chloride ions in and out of cells
It forms a gated chloride channel protein.
What is the mode of inheritance for Cystic Fibrosis?
Autosomal recessive
Carriers are unaffected, and incidence is higher in Caucasians.
What is the most common CF variant?
P.Phe508del
This variant involves a deletion of 3 nucleotides leading to a mis-folded protein.
What type of testing is used to diagnose Cystic Fibrosis?
Newborn bloodspot screening and sweat test
Heel prick checks the amount of IRT, a pancreatic enzyme.
What are some treatments for Cystic Fibrosis?
Anti-inflammatory drugs, antibiotics, lung transplant, mucolytics
Treatment aims to manage symptoms and improve quality of life.
What is a key symptom of Huntington’s Disease?
Motor dysfunction, including involuntary movements (chorea)
Symptoms typically start in mid 30-40s.
What gene is associated with Huntington’s Disease?
HTT gene
It is located on chromosome 4 and involves CAG expanded repeats.
What occurs when the HTT gene has more than 36 CAG repeats?
Produces a misfolded version of the huntingtin protein
This leads to cellular dysfunction and neurodegeneration.
What is the mode of inheritance for Huntington’s Disease?
Autosomal dominant
Incomplete penetrance means not all carriers will express symptoms.
What is the definitive diagnostic test for Huntington’s Disease?
Genetic testing for expanded CAG repeats in the HTT gene
Neuroimaging can also show structural brain changes.
What are dystrophinopathies?
Group of muscular diseases caused by pathogenic variants in the dystrophin (DMD) gene
Dystrophin is crucial for muscle cell integrity.
What is the primary mode of inheritance for Dystrophinopathies?
X-linked recessive
Primarily affects males; females may experience mild symptoms as carriers.
What are common symptoms of Duchenne Muscular Dystrophy (DMD)?
Progressive weakness, muscle atrophy, loss of coordination, breathing difficulties
Symptoms worsen with age.
What role does dystrophin play in muscle cells?
Links actin cytoskeleton to the extracellular matrix, stabilizing muscle fibers
It protects muscle fibers from damage during contraction.
What is the treatment for Dystrophinopathies?
No cure; treatments include corticosteroids, physical therapy, and ventilatory support
Medications may help manage symptoms and improve quality of life.
What is an important diagnostic tool for Dystrophinopathies?
Genetic testing for mutations in the dystrophin gene
Muscle biopsies may also be performed to assess dystrophin presence.
