Genetics Flashcards
What is personalised medicine?
The idea to use some form of testing to identify a subgroup of patients who respond to treatmet involving genetic testing and understanding molceular pathways
What does personlaised medicine allow you to do?
Separate patients into subgroups of those who will benefit frmo a treatment and exclude those who won’t or will have severe side effects
What clinical signs can be seen in the nails in tuberous sclerosis?
Periungual fibromata
Longitudinal ridging
What is a genodermatoses?
A skin condition caused by a genetic cause
How can tuberous sclerosis present in infants?
Infantile seizures
What is the earlisest cutaenous sign of tuberous sclerosis?
Ash-lead macule
What are all the clinical signs of tuberous sclerosis?
Periungual fibromas Facial angiofibromas Seizures due to tumours in the cortical brain Hamaromas - angiomyolipomas Bone cysts Shagreen patches Enamel pitting
What are angiofibromas often misdiagnosed as?
Acne (erythematous papules) but the defining difference as angiofibromas don’t have comedones
What type of inheritance does tuberous sclerosis show?
Autosomal dominant - denovo mutations are common
What chromosomes are affected in tuberous sclerosis?
Chromosome 9 and 16
TSC1 and TSC2 which code for tuberin and hamartin
What is the chance of passing on a mutation to offspring in classical autosomal dominance?
50-50 chance
What are the different mutation types?
Missence Deletion (in frame) Nonsense (premature stop codon) Deletion (frameshift) Altered splice site
For what conditions is using genetics the most useful in treatment of diseases?
In high penetrance disorders due to the fact that they tend to have one pathway and therefore one drug which can control it
What is genetic heterogeneity?
Mutations at two or more genetic loci that produce the same or similar phenotypes
What is disease expression variability?
Different people are affeced differently - even within the same family