Chapter 12.1: Rearrangements of Chromosomal DNA

Question 1

Define deletion

Answer 1

removing base pairs

Question 2

Define duplications

Answer 2

adding base pairs

Question 3

Define inversions

Answer 3

half-circle rotations of a chromosomal region

Question 4

What are half-circle rotations of a chromosomal region?

Answer 4

inversions

Question 5

Define reciprocal translocations

Answer 5

two nonhomologous chromosomes exchange parts

Question 6

What are two nonhomologous chromosomes exchange parts?

Answer 6

reciprocal translocations

Question 7

What causes chromosomal rearrangements?

Answer 7

o Deletions, inversions, duplications, and reciprocal translocations come about most often by either of two events: chromosomal breakage or aberrant (illegitimate) recombination at sites of repeated DNA sequences

Question 8

What type of chromosomal rearrangement occurs o If a single chromosome suffers two double-strand breaks, loss of the fragment between the breaks followed by DNA repair that fuses the remaining broken ends (nonhomologous end-joining) ?

Answer 8

deletion

Question 9

What type of chromosomal rearrangement occurs If a single chromosome suffers two double-strand breaks
followed by DNA repair that fuses the remaining broken ends (nonhomologous end-joining)
if the intervening fragment rotates by 180°
?

Answer 9

inversion

Question 10

What type of chromosomal rearrangement occurs o Breakage of two homologous chromosomes or sister chromatids at different locations can result in a if the broken chromosome ends change places before they are brought together by DNA repair?

Answer 10

deletion and a duplication

Question 11

What type of chromosomal rearrangement occurs when o Breakage of two nonhomologous chromosomes can result in if the broken ends switch places before repair and fusion

Answer 11

reciprocal translocation

Question 12

What type of chromosomal rearrangement occurs o Crossovers between repeats of the same sequence at two locations on the same chromosome can result in a if the repeats are in the same orientation?

Answer 12

deletion

Question 13

What type of chromosomal rearrangement occurs when o Crossovers between repeats of the same sequence at two locations on the same chromosome can result in a if the repeats are in opposite orientations

Answer 13

inversion

Question 14

What type of chromosomal rearrangement occurs o If two homologous chromosomes misalign at repeated sequences and cross over?

Answer 14

deletion and a duplication

Question 15

What type of chromosomal rearrangement occurs o Crossovers at a repeated sequence on two nonhomologous chromosomes

Answer 15

reciprocal translocations

Question 16

What are methods to detect chromosomal rearrangements?

Answer 16

o FISH techniques

o Microarrays of genomic DNA can be used to detect deletions or duplications too small to be found by barcoding

Question 17

Define rearrangement breakpoints

Answer 17

the base pairs at which the rearranged regions begins and ends

Question 18

What is the base pairs at which the rearranged regions begins and ends?

Answer 18

rearrangement breakpoints

Question 19

How are rearrangement breakpoints determined?

Answer 19

genome sequencing or PCR