L36

Question 1

How is HIV sequenced?

Answer 1

through PCR, isolating viral genomes

Question 2

How many sequences come from each patient in a tree of HIV?

Answer 2

Multiple

Question 3

What is the relation between squences and patients

Answer 3

Sequences are more closelesy related within a patient than between

Question 4

What can cause a tree of HIV sequences?

Answer 4

Multiple viruses
Viruses are changing

Question 5

What is the evidence for and against multiple viruses in patients?

Answer 5

For: Multiple sequences
against: Pattern of tree ( Why are viruses more similar in patients than between viruses

Question 6

What is the evidence for and prediction viruses changing?

Answer 6

for: Viruses within patient are more similar (diversification)

We can predict to see viruses changing overtime

Question 7

What are the two types of explanation for sequences changing?

Answer 7

Proximate: by what mechanisms
ultimate: what is causing the change

Question 8

What are the mechanisms of change?

Answer 8

Reverse transcription of viral genome

Question 9

What is reverse transcription and what enzyme facilitates it

Answer 9

Reverse Transcriptase turns RNA sequence into DNA

Error prone (so variants are formed)

Question 10

How can we confirm HIV evolves?

Answer 10

Changing slective pressures eg (drug immunity)

Question 11

What is the evidence for evolution of HIV in patitenst?

Answer 11

AIDS viruses. from patients using anti retrovirals have different pattern of variation

Question 12

How is HIV able to evolve quickly? and its consequences

Answer 12

Fast life cycles, means that its patients have viral variants

resistance to therapy making vaccines very hard