Genetics Flashcards
a 35-year-old lady presented with these lesions on her hands and feet -
epilepsy age 7yrs
normal intelligence
Periungual fibromata (tumours around nails) & longitudinal ridging
diagnosis?
tuberous sclerosis
tuberous sclerosis is one of the most common ____________
tuberous sclerosis is one of the most common GENODERMATOSES
what may tuberous sclerosis present with in infants?
infantile seizures
what is the earliest cutaneous sign in tuberous sclerosis?
ash-leaf macule
tuberous sclerosis is autosomal ________
tuberous sclerosis is autosomal DOMINANT
what are the facial tumours called in tuberous sclerosis and where are they most commonly found on the face?
facial angiofibromas
nasal labial folds
________ patches and ______ pitting may also be seen in tuberous sclerosis
SHAGREEN patches and ENAMEL pitting may also be seen in tuberous sclerosis
what causes the epilepsy/seizures in tuberous sclerosis?
cortical tubers
name the 2 important proteins and 2 important chromosomes in tuberous sclerosis
tuberin (chromosome 9) and hamartin (chromosome 16)
mTOR control what?
mTOR control cell division
what is the treatment for tuberous sclerosis?
topical rapamycin treatment
what has a:
(a) high penetrance but low frequency
(b) low penetrance but high frequency
(a) mutations - mendelian disorders
(b) SNPS and CNVs - common disorders
born at term after normal pregnancy
some skin loss noted
24 hours later - widespread blistering and skin loss
diagnosis?
epidermolysis bullosa (EB)
name the 3 types of EB
simplex
junctional
dystrophic
EB aquisita is a ____ __________ condition
EB aquisita is a RARE AUTOIMMUNE condition
autosomal dominant:
disease is seen in ___ generations
__% risk of affected child if parent is affected
autosomal dominant:
disease is seen in ALL generations
50% risk of affected child if parent is affected
autosomal recessive:
disease is often only seen in ___ generation
__% risk of affected child if parent is affected
autosomal recessive:
disease is often only seen in ONE generation
25% risk of affected child if parent is affected
14 year old boy presents with multiple asymptomatic coffee coloured flat marks which have been appearing over the last few years
general health is good with slight learning difficulties
diagnosis?
neurofibromatosis type 1
more than how many cafe au lait macules suggest genetic disease?
> 5
what are neurofibromas?
soft neural tumours
name the features of NFT1
cafe au lait neurofibromas plexiform neuroma axillary or inguinal freckling optic glioma 2 or more Lisch nodules a distinctive bony lesion
name the important protein in NFT1
neurofibromine
name the treatment for neurofibromatosis
MEK inhibitors
baby develops red, roughened patched sos skin at 2 weeks of age
at 9 months of age, the child’s skin is itchy & broken; sleep is disturbed because of scratching
throughout childhood there are itchy red patches of skin that come & go
diagnosis?
atopic eczema
name the important gene in atopic eczema and what mutations in it cause
filaggrin
mutations cause ichthyosis vulgaris (hyperliner palms)