Dysmorphology Flashcards
what does dysmorphology mean
dys - abnormal
morphology - study of stricture and form of either animals and plants or words and phrases
mainly study features own the face
what types of congenital defects are more likely to be genetic or not genetic
not - single malformations
genetic - multiple malformations
dysmorphic
family history of similar problems
what are 4 types of chromosomal disorders
syndromes: di George Williams down palmister - killian
describe DiGeorge syndrome
22q.11.2 deletion
1 in 5000
learning difficulties, cleft palate, congenital heart defect, hypocalcaemia (seizures), immune deficiency and renal malformation
describe williams syndrome
7q11 deletion (elastin gene)
1 in 20,000
learning difficulties
cocktail party speech - elaborate but meaningless
CHD - supravalvular aortic stenosis, peripheral pulmonary artery stenosis
hypercalcaemia
describe down syndrome
most common chromosomal disorder - trisomy 21 (extra) 1 in 800 learning difficulties sever CHD low muscle tone in babies (hypotonia) single palmar cease cataracts hearing impairment hypothyroidism leukaemia risk of Alzh
describe pallister - killian syndrome
mosaic teratology of 12p 5.1 per 1 mil developmental delay various congenital malformations mosaicism of the skin - hypo/hyper pigmentation blaschkos lines
name 7 mendelian disorders
achondroplasia beckwith - weidemann kabuki peutz-jeghers teacher-collins waardenburg smitho-lemmi optiz
describe achondroplasia
dwarfism
1 in 20,000
FGFR3 gene mutation (makes fibroblast growth)
autosomal dominant (sperm mutation rather than ovum)
risk increases with paternal age
Rhizomelia (limb shortening and short stature)
hydrocephalus
describe beck with-weidemann syndrome
overgrowth disorder 1 in 10,000 imprinting disorder overactivity of IGF-2 on short arm 11 (11p15) or no CDKN1C (inhibitor of cell proliferation) large tongue exomphalos hemihypertrophy (one side of body larger - scoliosis) neonatal hypoglycaemia increased risk of wilms tumour
describe kabuki syndrome
1 in 30,000 autosomal dominant condition - KMT2D poor growth learning difficulties hearing impair cleft palate premature breast development persistent fetal finger pads
describe peutz-jeghers syndrome
less than 1 in 50,000 familial - STK11 gene mutation down slanting eyes, abnormal ears hyperpigmentation around mouth gastrointestinal polyps malignancies freckling of lips
describe treacher-colins syndrome
1 in 50,000 autosomal dominant TCOF gene on chromosome 5 cleft palate face deformation hearing impair
describe waardenburg syndrome
1 in 250,000 sensorineural hearing impairment iris heterchromia - deep blue eyes premature greying white forelock hypo pigmentation congenital malformations
describe smitho-lemmi optic syndrome
autosomal recessive condition - inborn error of cholesterol synthesis - mutation in DHCR7
little normal cholesterol
very high fatty diet can reduce behavioural abnormality
