Dysmorphology Flashcards
what % of newborns have a birth defect?
3%
what is an anomaly?
limits: requires computer software, time-consuming to enter data; incorporate only FDR and SDR (may need to change proband to best capture risk)
what is a deformation?
compression or biomechanical distortion of a normally formed body part (typically happens after 8-10wks)
what is a disruption?
compression/biomechanical distortion of already formed (or to be formed) body part
- Severity makes it look like an anomaly
- I.e. amniotic band, webbed neck due to nuchal edema
what is a major anomaly?
- basic alteration in development
- Severe enough to require intervention, potentially has a long-term impact medically or psychologically
what is a minor anomaly?
basic change in development (embryo or fetus) that does not need treatment or can be (more or less) corrected
what is a minor/normal variant?
minor/normal variant feature -> low frequency (1-5%) feature in gen pop OR integral part of multiple congenital anomaly syndrome
i.e. Transverse palmar crease, 5th finger clinodactyly, 2-3 toe syndactyly, epicanthal folds, accessory nipple
what are some major features of Apert syndrome? gene? mutation causes?
craniosynostosis and complex syndactyly
FGFR2 (de novo - advanced paternal age effect)
how can we better determine the distance between eyes?
interpupillary distance
what are some of the features we can see with the pupil in conditions?
what conditions do you see Brushfield spots, Lisch nodules, stellate iris?
aniridia, coloboma
brushfield -> T21
Lisch -> NF1
Stellate iris -> Williams syndrome
how common are ear pits or tags? can be associated with what finding?
1: 90 overall
1: 200 with pits or tags can have SNHL
large tounges can be associated with what kinds of conditions?
overgrowth syndromes like BWS
what condition(s) can teeth point us to?
ectodermal dysplasia (delayed eruption, absent teeth, etc.)
what do we know about cleft lip and/or palate? what combination has the highest recurrence risk in a sib? lowest?
can be unliateral, bilateral or midline
can be isolated
the more severe the more likely it is to be syndromic
bilateral CL/P (8%)
unilateral cleft lip
what is spadias?
urethra is not located where it typically is
is arthrogryposis typically considered genetic?
not usually
what causes DiGeorge syndrome? major features?
microdeletion at 22q11.2
conotruncal heart defects, velopalatine dysfunction, typical facies, increased hypocalcemia and thmyic hypo-agenesis, increased frequency of LD and schizophrenia
what are the features seen in CHARGE syndrome? does everyone have all features?
coloboma heart defects atresia choanae (nose openings) retardation of growth/development genital defects ear anomalies and/or deafness
not all have all features
what evaluation is necessary for CHARGE?
very careful audiology workup
what is the most common gene associated with Noonan syndrome?
PTPN11
what condition is caused by a microdeletion at 7q11.23, known for their stellate irises, upturned nose, and dislike of loud sounds?
Williams syndrome
Which overgrowth syndrome is the most common and caused by an imprinting defect?
Beckwith-Wiedemann
people with BWS have an increased risk of:
embryonic tumors
what syndrome is characterized by hearing loss, a white forelock and dystopia canthorum?
Waardenburg syndrome type 1
how many types of Waardenburg syndrome are there?
4
What X-linked condition involves MECP2, typically shows symptoms beginning at 6-18mo and is characterized by a plateau and regression of skills?
Rett syndrome
