Genetics Flashcards
List the clinical features of tuberose sclerosis
Epilepsy, seizures Periungual fibromata (messed up nails) Longitudinal ridging Ash-leaf macule Enamel pitting (in teeth)
Tuberose sclerosis is autosomal recessive. True/False?
False
High penetrance autosomal dominant
What is meant by non-penetrance?
Having the mutation but not having features of the disease
In autosomal dominance, what is the % risk of affected child if a parent is affected?
50%
Which genes become mutated to cause tuberose sclerosis?
TSC1
TSC2
N.B. only either 1 or 2 becomes mutated
Which inhibitors partially correct tuberose sclerosis?
mTOR inhibitors
Tuberose sclerosis is a common disorder. True/False?
False
It is a high penetrance Mendelian disorder (so not common)
What is epidermolysis bullosa?
A group of genetic skin fragility conditions involving blistering and erosion
‘Blistering at birth’
Due to faulty skin structure and adhesions
Simplex EB affects ?
Junctional EB affects ?
Dystrophic EB affects ?
Simplex EB affects epidermis
Junctional EB affects DEJ
Dystrophic EB affects dermis
What is meant by haploinsufficiency disease?
One gene can’t produce the protein, so you end up with less protein overall
What is the most common genetic dermatological condition? What inheritance pattern does it have?
Neurofibromatosis type 1
Autosomal dominant
How does a mutated NF1 gene cause neurofibromatosis?
NF1 is responsible for switching off cell cycle
Mutated NF1 therefore promotes excessive cell proliferation
List clinical features of neurofibromatosis
Café-au-lait macules Neurofibromas (soft neutral tumours) Axillary/inguinal freckling Lisch nodules Optic glioma Distinctive bony lesion
What is the management for tuberous sclerosis ?
Topical rapamycin
What is the management for neurofibromatosis?
MEK inhibitors
