Abnormal Segregation Disorders

Question 1

Chromosomes involved in Robertsonian translocations

Answer 1

13, 14, 15, 21, and 22

Question 2

Karyotypes allows for the detection of

Answer 2

aneuploidy/polyploidy
large structural changes

Question 3

Type of cells used in Karyotyping

Answer 3

metaphase

Question 4

Polyploidy

Answer 4

extra complete sets of chromosomes

Question 5

Aneuploidy

Answer 5

extra or missing of one or more chromosomes

Question 6

isochromosomes

Answer 6

loss of part of one chromosome and duplication of another

Question 7

Rate reciprocal translocations are inherited from healthy parent

Answer 7

70%

Question 8

Rate of de novo chromosomal ring

Answer 8

99%

Question 9

Primary origin of non-mosaic aneuploidy

Answer 9

maternal meiosis I non-disjunction

Question 10

Frequency at birth for trisomy 21

Answer 10

1/800 live births

Question 11

Frequency for 47,XXY

Answer 11

1/700 male births

Question 12

Frequency of 47,XYY

Answer 12

1/700 male births

Question 13

Frequency of 47,XXX

Answer 13

1/1000 female births

Question 14

Frequency of 45X

Answer 14

1/1-3000 females

Question 15

Frequency of trisomy 18

Answer 15

1/8000 live births

Question 16

frequency of trisomy 13

Answer 16

1/20,000 live births

Question 17

Frequency of translocations

Answer 17

1/500

Question 18

Birth defects associated with T21

Answer 18

CHD (AV canal, VSD, ASD) (50%)
GI- 12%

Question 19

Key findings in Edward’s syndrome

Answer 19

Central hypertonia, overlapping fingers, rocker-bottom feet

Question 20

Birth defects associated to Edward’s syndrome

Answer 20

CHD, PKD

Question 21

Birth defects associated with T13/Patau syndrome

Answer 21

omphalocele, CHD, PKD, CNS malformation