CHAPTER 30: CYTOGENETICS

Question 1

(1) G-banding refers to the technique of staining chromosomes:

a. To isolate those in the G group (i.e., chromosomes 21 and 22)
b. In the G0 or resting stage
c. Using Giemsa stain
d. To emphasize areas high in guanine residues

Answer 1

c. Using Giemsa stain

Question 2

(2) Which of the following compounds is used to halt mitosis in metaphase for chromosome analyses?

a. Imatinib
b. Fluorescein
c. Trypsin
d. Colchicine

Answer 2

d. Colchicine

Question 3

(3) One arm of a chromosome has 30 bands. Which band would be nearest the centromere?

a. Band 1
b. Band 15
c. Band 30

Answer 3

a. Band 1

Question 4

(4) Which of the following is not an advantage of the use of FISH?

a. It can be used on nondividing cells.
b. It can be used on paraffin-embedded tissue.
c. It can detect mutations that do not result in abnormal banding patterns.
d. It must be performed on dividing cells

Answer 4

d. It must be performed on dividing cells

Question 5

(5) Which of the following types of mutations would likely not be detectable with cytogenetic banding techniques?

a. Point mutation resulting in a single amino acid substitution
b. Transfer of genetic material from one chromosome to another
c. Loss of genetic material from a chromosome that does not appear on any other chromosome
d. Duplication of a chromosome resulting in 3n of that genetic material

Answer 5

a. Point mutation resulting in a single amino acid substitution

Question 6

(6) Which of the following describes a chromosomal deletion?

a. Point mutation resulting in a single amino acid substitution
b. Transfer of genetic material from one chromosome to another
c. Loss of genetic material from a chromosome that does not appear on any other chromosome
d. Duplication of a chromosome resulting in 3n of that genetic material

Answer 6

c. Loss of genetic material from a chromosome that does not appear on any other chromosome

Question 7

(7) The chromosome analysis performed on a patient’s leukemic cells is reported as 47, XY,+4,del(5)(q31)[20].

This patient’s cells have which of the following mutations?

a. Loss of the entire number 31 chromosome
b. Loss of the entire number 5 chromosome
c. Loss of a portion of the short arm of chromosome 4
d. Loss of a portion of the long arm of chromosome 5

Answer 7

d. Loss of a portion of the long arm of chromosome 5

Question 8

(8) The chromosome analysis performed on a patient’s leukemic cells is reported as 47, XY,+4,del(5)(q31)[20].

What other mutation is present in this patient’s cells?
a. Polyploidy
b. Tetraploidy
c. An extra chromosome 4
d. Four copies of chromosome 5

Answer 8

c. An extra chromosome 4

Question 9

(9) The chromosome analysis performed on a patient’s leukemic cells is reported as 47, XY,+4,del(5)(q31)[20].

This patient’s leukemic cells demonstrate:
a. Structural chromosomal defects only
b. Numeric chromosomal defects only
c. Both structural and numeric chromosomal defects

Answer 9

b. Numeric chromosomal defects only

Question 10

(10) Aneuploidy describes the total chromosome number:

a. That is a multiple of the haploid number
b. That reflects a loss or gain of a single chromosome
c. That is diploid but has a balanced deletion and duplication of whole chromosomes
d. In gametes; diploid is the number in somatic cells

Answer 10

b. That reflects a loss or gain of a single chromosome