Dysmorphology

Question 1

what % of newborns have a birth defect?

Answer 1

3%

Question 2

what is an anomaly?

Answer 2

limits: requires computer software, time-consuming to enter data; incorporate only FDR and SDR (may need to change proband to best capture risk)

Question 3

what is a deformation?

Answer 3

compression or biomechanical distortion of a normally formed body part (typically happens after 8-10wks)

Question 4

what is a disruption?

Answer 4

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

Question 5

what is a major anomaly?

Answer 5

• basic alteration in development

- Severe enough to require intervention, potentially has a long-term impact medically or psychologically

Question 6

what is a minor anomaly?

Answer 6

basic change in development (embryo or fetus) that does not need treatment or can be (more or less) corrected

Question 7

what is a minor/normal variant?

Answer 7

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

Question 8

what are some major features of Apert syndrome? gene? mutation causes?

Answer 8

craniosynostosis and complex syndactyly

FGFR2 (de novo - advanced paternal age effect)

Question 9

how can we better determine the distance between eyes?

Answer 9

interpupillary distance

Question 10

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?

Answer 10

aniridia, coloboma

brushfield -> T21

Lisch -> NF1

Stellate iris -> Williams syndrome

Question 11

how common are ear pits or tags? can be associated with what finding?

Answer 11

1: 90 overall
1: 200 with pits or tags can have SNHL

Question 12

large tounges can be associated with what kinds of conditions?

Answer 12

overgrowth syndromes like BWS

Question 13

what condition(s) can teeth point us to?

Answer 13

ectodermal dysplasia (delayed eruption, absent teeth, etc.)

Question 14

what do we know about cleft lip and/or palate? what combination has the highest recurrence risk in a sib? lowest?

Answer 14

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

Question 15

what is spadias?

Answer 15

urethra is not located where it typically is

Question 16

is arthrogryposis typically considered genetic?

Answer 16

not usually

Question 17

what causes DiGeorge syndrome? major features?

Answer 17

microdeletion at 22q11.2
conotruncal heart defects, velopalatine dysfunction, typical facies, increased hypocalcemia and thmyic hypo-agenesis, increased frequency of LD and schizophrenia

Question 18

what are the features seen in CHARGE syndrome? does everyone have all features?

Answer 18

coloboma
heart defects
atresia choanae (nose openings)
retardation of growth/development
genital defects
ear anomalies and/or deafness

not all have all features

Question 19

what evaluation is necessary for CHARGE?

Answer 19

very careful audiology workup

Question 20

what is the most common gene associated with Noonan syndrome?

Answer 20

PTPN11

Question 21

what condition is caused by a microdeletion at 7q11.23, known for their stellate irises, upturned nose, and dislike of loud sounds?

Answer 21

Williams syndrome

Question 22

Which overgrowth syndrome is the most common and caused by an imprinting defect?

Answer 22

Beckwith-Wiedemann

Question 23

people with BWS have an increased risk of:

Answer 23

embryonic tumors

Question 24

what syndrome is characterized by hearing loss, a white forelock and dystopia canthorum?

Answer 24

Waardenburg syndrome type 1

Question 25

how many types of Waardenburg syndrome are there?

Answer 25

4

Question 26

What X-linked condition involves MECP2, typically shows symptoms beginning at 6-18mo and is characterized by a plateau and regression of skills?

Answer 26

Rett syndrome