Chromosomes to Bases

Question 1

how many chromosomes does a normal human have?

Answer 1

46

Question 2

what does 46 XX mean?

Answer 2

female

Question 3

what does 46 XY mean?

Answer 3

male

Question 4

how can chromosomes be recognised?

Answer 4

banding patterns
length
position of the centromere

Question 5

describe the overall structure of a chromosome

Answer 5

telomeres at either end
short arm (p) and long arm (q)
centromere between the arms

Question 6

what is an acrocentric chromosome?

Answer 6

one where the short arm is so small it is negligible

Question 7

what are the two types of chromosome rearrangements?

Answer 7

balance

unbalanced

Question 8

what is a balanced chromosome rearrangement?

Answer 8

all chromosomal material is present

Question 9

what is an unbalanced chromosome rearrangement?

Answer 9

extra or missing chromosomal material

Question 10

what is aneuploidy?

Answer 10

a whole extra or missing chromosome

Question 11

what is translocation?

Answer 11

rearrangement or chromosomes

Question 12

what are insertions and deletions?

Answer 12

missing or duplicated material

Question 13

what is 47 XY + 21?

Answer 13

Down syndrome

Question 14

what is a robertsonian translocation?

Answer 14

when two acrocentric chromosomes are stuck end to end

Question 15

what chromosomes can be affected by robertsonian translocation?

Answer 15

14

21

Question 16

what does trisomy 14 cause?

Answer 16

miscarriage

Question 17

what does trisomy 21 cause?

Answer 17

Down syndrome

Question 18

what does trisomy 18 cause?

Answer 18

Edwards syndrome

Question 19

what is 47 XY+18?

Answer 19

edwards syndrome

Question 20

what is 45 X?

Answer 20

Turner syndrome

Question 21

why is X chromosome aneuploidy better tolerated than others?

Answer 21

due to X inactivation

Question 22

what is 47 XXX?

Answer 22

triple X

Question 23

what is 47 XXY?

Answer 23

klinefelter syndrome

Question 24

what is a reciprocal translocation?

Answer 24

when parts of two chromosomes are swapped

Question 25

what is the first line chromosomal genetic test?

Answer 25

array CGH

Question 26

what type of rearrangements can be detected by aCGH?

Answer 26

unbalanced

Question 27

how could chromosome changes result in malignancy?

Answer 27

activation of an oncogene | deletion of a tumour suppressor

Question 28

what is the management of a malignancy with HER2 amplification?

Answer 28

trastuzamab

Question 29

what is the treatment in a malignancy with a Philadelphia chromosome?

Answer 29

imatinib