Genetics Flashcards
A 35yo lady presents with periungual fibromata and longitudinal ridging on hands and feet, epilepsy from 7yo and normal intelligence, diagnosis?
Tuberose Sclerosis
What is the earliest cutaneous sign of Tuberose Sclerosis?
Ash-leaf macule
Where will periungual fibromas be found?
Around nails
What tumours may be found in Tuberose Sclerosis?
Periungual fibromas, facial angiofibromas, cortical tubers and/or calification of falx cerebri, hamartomas, bone cysts
What can cortical tubers cause?
Epilepsy, mental impairment (to varying degrees)
What type of genetic disorder is Tuberose Scleroris?
Autosomal Dominant
The genes TSC 1/2 are involved in Tuberose Sclerosis, what do they code for?
Tuberin and hamartin
What does Epidermolysis Bullosa describe?
A group of genetic skin fragility conditions. Dominant,recessive, new mutation or acquired with variable severity
What are the 3 main types of Epidermolysis Bullosa?
Simplex, junctional and dystrophic
How many genes are involved in Epidermolysis Bullosa?
10
What overall aspects of the skin are effected by Epidermolysis Bullosa?
Structure and adhesion
What does a dominant-negative disease mechanism cause in terms of protein fomation?
Aggregates are formed instead of filaments with the mutant gene
What does a Haploinsufficiency (dominant) disease mechanism cause in terms of protein formation?
Less protein formed
What does a Recessive disease mechanism cause in terms of protein formation?
No protein formed
What does haploinsufficiency mean?
Only one copy of working gene- reduced protein production
