2 - genetic skin diseases

Question 1

what does haploinsufficiency mean?

Answer 1

means only 1 copy working (reduced protein production)

Question 2

what does dominant negative mean?

Answer 2

means expression of abnormal protein interferes with normal protein

Question 3

what is neurofibromatosis?

Answer 3

= genetic condition (from NF1 gene) causing tumours along nervous system

Question 4

what is presentation of neurofibromatosis?

Answer 4

• lots of lumps everywhere
• cafe au lait macules
• axillary or inguinal freckling (weird areas since don’t see sun)
• 2 or more lisch nodules (brown spots on eyes)

Question 5

what is tuberous sclerosis?

Answer 5

it’s genetic condition where get lots of benign tumours in loads different organs
= autosomal dominant

Question 6

what is clinical presentation of tuberous sclerosis?

Answer 6

= different for each person, can vary where get tumours and that makes difference on symptoms

• might present as infantile seizures
• ash leaf macules = earliest cutaneous sign
• shagreen patches & enamel pitting

Question 7

what are tumours you can get in tuberous sclerosis?

Answer 7

• periungual fibromas (around nails)
• facial angiofibromas (look like acne but in 1st few years)
• cortical tubers & calcification of falx cerebri (cause seizures)
• haemartomas & angiomyolipoma

Question 8

what is epidermolysis bullosa? what are 3 types?

Answer 8

group of inherited disorders with skin fragility meaning blister formation more likely on mechanical trauma

3 types = simplex, junctional, dystrophic