Down

Question 2

What Characterizes Complete Trisomy 21?

Answer 2

The Most Common

Question 3

Complete Trisomy 21

• Karyotyping

Answer 3

47,XX + 21

Question 4

Incidence of Complete Trisomy 21

Answer 4

Question 5

What Is Complete Trisomy 21 dependent on?

Answer 5

Maternal Age

Question 6

Cause of Complete Trisomy 21

Answer 6

• Non-disjunction of chromosome 21 during meiotic division (80 % in maternal meiosis I)
• lt occurs during oogenesis more than spermatogenesis.

Question 7

Mosaic Down Syndrome

• Karyotyping

Answer 7

47, XX + 21 / 46, XX

Question 8

Translocation Down Syndrome

• Karyotyping

Answer 8

46,XX, t(14q, 21q)

Question 9

D/21 Translocation

Answer 9

Question 10

• lf ovum contains translocation chromosome only, fertilization by normal sperm will Iead to …..

Answer 10

BTC —> (45 chromosome but genome of 46 chromosomes)

Question 11

• lf ovum contains translocation chromosome and normal chromosome 21, fertilization by normal sperm will lead to …..

Answer 11

Down syndrome (46 chromosome but genome of 47 chromosomes)

Question 12

G/21 Translocation

Answer 12

Question 13

Down Syndrome

• Constant Features

Answer 13

• Delayed physical growth
• Delayed mental development (mild to moderate mentaI retardation)
• Hypotonia

Question 14

CP of Down Syndrome

• Head

Answer 14

Question 15

CP of Down Syndrome

• Eyes

Answer 15

Question 16

CP of Down Syndrome

• Nose

Answer 16

Small with depressed nasal bridge

Question 17

CP of Down Syndrome

• Ears

Answer 17

• Small
• Low set & backward displacement

Question 18

CP of Down Syndrome

• Neck

Answer 18

Short & Webbed

Question 19

CP of Down Syndrome

• Tongue

Answer 19

• Protruded (small oral cavity)
• Fissured (scrotal)

Question 20

CP of Down Syndrome

• Ribs

Answer 20

Unilateral or bilateral absence of one rib

Question 21

CP of Down Syndrome

• Hands

Answer 21

Question 22

Def of Brachydactyly

Answer 22

Short + stocky

Question 23

Def of Clinodactyly

Answer 23

lncurved little fingers

• Due to rudimentary or absent mid phalanx of
  little finger)。

Question 24

Def of Simian Crease

Answer 24

Transverse palmer crease (partial or complete)

Question 25

CP of **Down Syndrome** - Feet

Answer 25

Question 26

CP of **Down Syndrome** - GIT & Abdomen

Answer 26

Question 27

CP of **Down Syndrome** - CoHD

Answer 27

Question 28

CP of **Down Syndrome** - Endocrine

Answer 28

Question 29

CP of **Down Syndrome** - Genitalia

Answer 29

Poorly developed

Question 30

CP of **Down Syndrome** - Immunity

Answer 30

Impaired cellular & humeral immunity

Question 31

Complications of **Down Syndrome**

Answer 31

Question 32

Most Common Causes of Death **Down Syndrome**

Answer 32

- Accidents due to mental retardation - Sudden death due to arrhythmia

Question 33

Most Common Presentation of complication **Down Syndrome**

Answer 33

- Heart failure due to congenital heart disease - Recurrent chest infections due to CHD, i immunity, most common presentation Hypotonia, aspiration & Decreased immunity **(Predominantly T cell dysfunction, however, both T & B cells functions are affected)**

Question 34

INVx for **Down Syndrome**

Answer 34

- Prenatal - After Birth

Question 35

INVx for **Down Syndrome** - Prenatal Dx

Answer 35

Question 36

INVx for **Down Syndrome** - Prenatal Dx (1st Trimester)

Answer 36

Question 37

INVx for **Down Syndrome** - Prenatal Dx (2nd Trimester)

Answer 37

Question 38

Maternal Serum Screening in 2nd Trimester for **Down Syndrome**

Answer 38

Question 39

INVx for **Down Syndrome** - After Birth

Answer 39

Question 40

DDx of **Down Syndrome**

Answer 40

Question 41

Managment Plan for **Down Syndrome**

Answer 41

Question 42

Genetic Counseling for **Down Syndrome**

Answer 42