Tecniques Of Genetic Analysis

Question 1

What other situation is mandatory to ask PCR to detect HIV infection rather than ELISA or WB?

Answer 1

Early testing after known exposure to HIV-positive blood (ex; needle sticks) or other fluids/tissue

Question 2

What test is used to study infants whose mothers are HIV positive? In what time of age?

Answer 2

PCR (test for the integrated proviral genome, HIV DNA PCR)
- advantages:
✔️(+) much earlier after infection
✔️Doesn’t rely on an Ab response
*useful because antibody test is uninformative (ELISA and WB)
*from birth until 18 month

Question 2

What test is use to measure the concentration of viral load in AIDS patient?

Answer 2

Reverse transcriptase PCR (HIV RNA Assay)

Question 3

What is and uses of a short tandem repeats (STR)?

Answer 3

Repeats of di- to tetra nucleotide sequence (spacer, between and within gene regions)
- uses: as known and documented in chromosome maps, use to genetic testing (Test for CAG repeat in Huntington disease by PCR)

Question 4

What is a RFLP and its utility?

Answer 4

• Mutations in restriction endonuclease sites (DNA restriction fragments)
• Southern blot
• infer presence of a disease-causing allele of a gene in a family. Ex; sickle cell anemia - its mutation destroys a restriction site endonuclease.