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Flashcards in Genetics Deck (18):
1

What is precision medicine

The idea that you can personalise treatment in order to get the best outcome
Using genetics etc you could identify the patients that would benefit from treatment and those that wouldn't
Currently only available in some situations

2

What is the earliest cutaneous sign of tuberous sclerosis

Ash-leaf macule
depigmented macule in rough leaf shape

3

What is a common first presentation of tuberous sclerosis

Infantile seizures

4

What is a genodermatoses

skin condition caused by a well defined genetic cause

5

what are angiofibromas

fibrous growth
associated with tuberous sclerosis
commonly seen in nasolabial folds

6

What are some skin signs of tuberous sclerosis

Ash- leaf macule
Angiofibroma
Shagreen patches - areas of raised nodules and redness
Enamel pitting

7

What are some non-skin related signs of tuberous sclerosis

Cortical tubers in brain - may cause seizures
Bone cysts
periungual fibromas - around nails

8

What are the penetrance and expression patterns for tuberous sclerosis

Penetrance is high
Still variable - some may not show features

Expression is variable so people are affected differently

9

How does epidermolysis bullosa first present

Usually some skin trauma at birth
Progresses to blistering and skin loss - especially after movement or handling
However, blistering at birth doesn't determine prognosis

10

What is the mitten deformity

Common in epidermolysis bullosa
Repeated skin loss/trauma causes a lot of scarring (repeated healing)
This can cause tightening of the skin on the hands and lead to the fingers losing mobilty or becoming fused

11

which genes are involved in epidermolysis bullosa

There are 10 genes
They are all involved in skin structure and adhesion
E.g. keratin 5, 14, integrins, collagen 17

12

What is the dominant-negative disease mechanism

where the mutation still allows protein to be made but it doesn't function properly
This abnormal polypeptide interferes
with the normal protein

13

If parents are both carriers of a recessive gene, what is the risk of the child being affected

1 in 4
More likely in cases of incest

14

what are café au lait macules

pigmented brown macules
occur from birth onwards
Can be normal if only 1 or 2
If more than 5 it suggests a genetic disease

15

what is a possible treatment for neurofibromas

MEK inhibitors
blocks the exaggerated pathway

16

What is the role of the filaggrin gene

Important in maintaining the skin barrier
filament aggragating protein

17

What condition occurs when there are mutations in the filaggrin gene

Ichthyosis vulgaris
Dry skin
Keratosis pilaris - bumps on back of arms
Wrinkled palms

18

Which conditions does a filaggrin mutation increase your risk of getting

Eczema x4
Asthma and hay fever x3
Peanut allergy x5