Deletion/Duplication

Question 1

[Gene/Chr del/5p]

Characteristics of 5p deletion (Cri du chat syndrome)? (6)

Answer 1

1. High-pitched cry
2. Facial features: hypertelorism, low-set ears, micrognathia,
3. Low birth weight
4. Intellectual disability, microcephaly
5. Hypotonia
6. Heart defect

Question 2

[Gene/Chr del]

Genetic cause of Wolf-Hirschhorn syndrome?

Answer 2

Heterozygous deletion of the Wolf-Hirschhorn syndrome critical region (WHSCR)
on chromosome 4p16.3

Question 3

[Gene/Chr del/4p]

Name of the syndrome with ‘greek warrior helmet’ face and Characteristics? (5)

Answer 3

4p deletion syndrome (Wolf-Hirschhorn syndrome)

1. Growth: prenatal-onset, postnatal growth retardation
2. Neuro: hypotonia with muscle underdevelopment, developmental delay/intellectual disability, seizures,
3. Auditory: hearing loss (mostly conductive)
4. Skeletal: skeletal anomalies (60%-70%)
5. Heart: congenital heart defects (~50%)

Question 4

[Gen/Microdel]

Name of syndrome?
With cocktail party personality, short stature

Answer 4

Williams syndrome (del 7q11.23)

Question 5

[Gen/Microdel]

7q11.23 deletion causes?

Answer 5

Williams Syndrome

Question 6

[Gen/Microdel/Williams]

Facial characteristics of Williams syndrome (del 7q11.23)? (5)

Answer 6

1. Broad forehead
2. Periorbital fullness
3. Shortened, upturned nose, flat nasal bridge
4. Elongated philtrum
5. Down-turned lower lip, wide mouth with full lips

Question 7

[Gen/Microdel/Williams]

Eye findings of Williams (7q11.23)? (2)

Answer 7

1. Stellate pattern of the iris
2. Strabismus

Question 8

[Gen/Microdel/Williams]

Neurologic/behavioral characteristics of Williams (del 7q11.23) (3)

Answer 8

1. Friendly
2. Intellectual disability
3. Hypersensitivity to sounds

Question 9

[Gen/Microdel/Williams]

Heart anomalies Williams (del 7q11.23)?

Answer 9

Supravalvular aortic stenosis

Question 10

[Gen/Microdel/Williams]

Endocrine/connective disorders of Williams (del 7q11.23) (3)

Answer 10

1. Hypercalcemia
2. Connective tissue disorder
3. Growth delay and short stature

Question 11

[Gen/Microdel/Williams]

Causal gene of connective disorder for Williams (del 7q11.23)

Answer 11

Elastin gene (ELN)

Question 12

[Gen/Microdel/WAGR]

WAGR (11p13 del) syndrome stands for?

Answer 12

Wilms tumor
Aniridia
Genitourinary malformation
Reduced intellectual abilities

Question 13

[Gen/Microdel/WAGR]

Gene Deletion of WAGR syndsrome?

Answer 13

11p13

Question 14

[Gen/Microdeletion]

Deletion of 11p13 causes?

Answer 14

WAGR syndrome

Question 15

[Gen/Microdel/WAGR]

Causal genes for WAGR syndrome (del 11p13)? (2)

Answer 15

PAX6
WT1 (wilms tumor 1)

Question 16

[Gen/Microdel/WAGR]

___ % of WAGR patients develop wilms tumor by ___ years old

Answer 16

50 % of WAGR patients develop wilms tumor by 3 years old

Question 17

[Gen/Microdel/WAGR]

Genital anomalies of WAGR syndrome (del 11p13)? (5)

Answer 17

1. Hypospadias
2. Cryptorchidism
3. Small penis
4. Hypoplastic scrotum
5. Gonadoblastoma

Question 18

[Gen/Microdel/WAGR]

Facial characteristics of WAGR syndrome (del 11p13)? (5)

Answer 18

1. Long face
2. Upward-slanting palpebral fissures
3. Ptosis
4. Beaked nose
5. Poorly formed ears

Question 19

[Gen/Microdel]

Most common microdeletion syndrome?

Answer 19

Del 22q11.2 (DiGeorge)

Question 20

[Gen/Microdel/22q11]

CATCH22 mnemonic for 22q11 deletion (DiGeorge)

Answer 20

Cardiac defect
Abnormal facies
Thymic hypoplasia (immune deficiency)
Cleft defects
Hypocalcemia (parathyroid gland hypoplasia)

Question 21

22q11.2 deletion syndrome
De novo vs inherited (%)

Answer 21

De novo: 90 %
Inherited: 10 %

Question 22

Responsible gene for 22q11.2 deletion syndrome

Answer 22

TBX1
(T box 1 transcription factor C)

Question 23

[Gen/Microdel/22q11]

What defect in fetal development causes 22q11.2 deletion (DiGeorge) phenotypes?

Answer 23

3rd and 4th pharyngeal pouches
(Abnormal development of the pharyngeal arches related to TBX1 dosage)

Question 24

[Gen/Microdel/22q11]

Cardiac defects of 22q11.2 deletion (DiGeorge) (from the most common) (4)

Answer 24

1. TOF
2. Interrupted aortic arch
3. VSD
4. Truncus arteriosus

Question 25

# [Gen/dup/CES] Characteristics of cat eye syndrome (5)?

Answer 25

1. eyes (iris coloboma) 2. ears (preauricular pits and/or tags) 3. anal region (anal atresia) 4. heart and kidneys 5. Intellectual disability (mild or borderline normal)

Question 26

# [Gen/dup/CES] Cause of cat eye syndrome (2)?

Answer 26

2/3: partial tetrasomy of 22pter-22q11(small supernumerary bisatellited marker chromosome) 1/3: this extra chromosome in mosaicism

Question 27

Which syndrome? partial tetrasomy of 22pter-22q11

Answer 27

Cat eye syndrome