Lecture 6

Question 1

Test for transforming genes

Answer 1

Transfection assay

Question 2

What are Alu sequences?

Answer 2

Highly repetitive sequences widely dispersed in human DNA but absent from mouse DNA (may therefore be used as a tag for the presence, location & cloning of human genes transferred into mouse cells)

Question 3

Karyotypic abnormalities in neoplasia

Answer 3

• Translocations
• Duplications
• Deletions
• Loss of chromosome

Question 4

Translocation event in ~90% of CML cases

Answer 4

Small Chr22

Question 5

Myc translocation in Burkitt’s lymphoma

Answer 5

Chr8 (site of myc gene) → Chr14
IgG heavy locus on Chr14 → Chr8

Question 6

Amplified DNA is often described as __ or __

Answer 6

double minutes (dm) or homogeneously staining regions (hsr)

Question 7

What are double minutes?

Answer 7

Small chromosome-like structures that lack centromeres

Question 8

What are homogeneously staining regions?

Answer 8

Amplified regions of the chromosome that stain homogeneously rather than yielding a pattern of bands

Question 9

Double minutes may integrate into the chromosome to form __

Answer 9

hsr

Question 10

C-myc amplified ~10 fold in which cell line?

Answer 10

Human promyelocytic cell line (HL-60)
- also amplified in breast, stomach & lung cancers

Question 11

C-myc amplification occurs in ~30% of __ cancers

Answer 11

breast

Question 12

What oncogene is amplified in ~20% of human breast cancers?

Answer 12

int-2 (also in squamous & gastric cancers)

Question 13

What related gene is sometimes co-amplified with int-2?

Answer 13

hst

Question 14

What family of proteins do int-2 and hst belong to?

Answer 14

The fibroblast growth factor (FGF) family