30b. Applications

Question 1

what does southern blotting tell you about geneticv variation in DNA? 3 points

Answer 1

1. the presense of a DNA sequence if it compliments the probe
2. the length of the DNA fragment
3. detection of restricting fragement length polymorphism (RFLP)

Question 2

what is RFLP?

Answer 2

shows variation in DNA sequences

Question 3

what does FISH tell you about genetic variation in DNA?

Answer 3

• the fluorescent labelled probe can locate the sepcfic DNA sequence on the chromosome
• detect deletions and duplication

Question 4

how can you prepare chromosomes with FISH? 3 steps

Answer 4

1. use a hyptonic buffer to isolate cells
2. drop onto microscope slide
3. incubate chromosomes + probe

Question 5

how does PCR indicate if genetic variation is present? 1 point

Answer 5

• amplifies the region containing allelic variation and then detect if the variation is present

Question 6

how are SNP and RFLP related?

Answer 6

SNPs can create RFLP because a restriction site can be present in one allele but absent in another