Clinical Aspects Flashcards
(37 cards)
What IQ for LD, mild, moderate, severe?
<70= LD. Mild= 50-70
Moderate 35-50
Severe 20-40
Profound <20
What is the functional definition for LD?
Dysfunction or impairment in >2 areas of communication, work, self care or social skills
% of unknown causes for LD (mild and severe)
80% for mild
30-50% severe
What 3 areas is dysmorphology concerned with?
1) deformation eg. Excessive moulding
2) disruption eg breakdown of normal development
3) malformation- eg isolated cleft lip and/or palate
Words for
1) shortening of proximal limbs
2) shortening of distal limbs
3) shortening of digits
1) rhizomelic
2) mesomelic
3) acromelic
What does syndactyly mean?
Joined together
What does USPF and DSPF mean ?
Upslanting palpebral fissures (corner of ur eyes)
Downslanting palpebral fissures
Indications for chromosome analysis
1) developmental delay
2) IUGR/ failure to thrive
3) microcephalic
4) facial dysmorphism
5) multiple congenital malformations
2 or more required
6% of unexplained mr is due to what?
Cryptic telomeric rearrangement - can test with multi probe fish
How many fragile sites in humans? What are they sensitive to?
>
- Sensitive to folate
Where is FRAXA and FRAXE?
FRAXA = Xq27.3 FRAXE = Xq28
What is the Sherman paradox?
Risk of developing mr is dependent on the individuals position in the pedigree with risk increasing in later generations
Characteristics of Fragile x: occurrence, when does classic features evolve, facial features, behaviour.
1 in 5,500 boys
Evolves at puberty
Long face, prominent ears, large nose
IQ 40, hyperactivity, impulsiveness, hand flapping
What causes fragile x?
cGG trinucleotide repeat in 5’UTR of FMR1 within non coding exon 1.
What is FXTAS? What are symptoms?
Fragile x associated tremor and ataxia syndrome.
Late onset progressive cerebellum ataxia and intention tremor in makes with permutations.
Peripheral neuropathy, short term memory loss, muscle weakness and autonomic dysfunction
Occurrence in f FXTAS in males and females?
40-45% of males
8-16.5% of females
What size permutations are at risk of expansion to full mutation?
52-70 repeats - no chance
80-89 76% risk
100+ 100% risk
What causes FRAXE and when is it tested for?
GCC expansion in FMR2 on Xq28
Tested if family history of x linked mental retardation
What % of patients with LD have a cytogenetic abnormality?
16%
After downs, patau and Edwards what are th most common autosomal trisomies (mosaic)
8 and 9
True or false: no autosomal monosomy is viable at term
True
What trisomy is the most common cause of spontaneous miscarriage?
Trisomy 16
What is the most common cause of DS?
Non dysjunction event at maternal meiosis 1st division 94%
Second most common cause f DS?
Unbalanced robertsonian translocation =4%
