Lab Techniques

Question 1

ELISA

Answer 1

• enzyme-linked immunosorbent assays
• mix human blood cells with enzymes and antibodies
• quickest and easiest way to test presence of an antibody in a patient’s serum
• often used to test for HIV

Question 2

Process to test for presence of HIV using ELISA

Answer 2

(1) apply human serum to a plate that contains HIV antigens
* if anti-HIV antibodies are present in serum then they bind to the to the HIV antigens*
(2) plate is washed and secondary antibody specific for human antibodies is applied
(3) secondary antibody is covalently bound to an enzyme that produces a color change upon application of its substrate or to a molecule that will fluoresce

Question 3

FISH

Answer 3

• fluorescence in situ hybridization
• used to search and find a specific DNA sequence on chromosomes
• use of PCR amplification to generate a supply of necessary probes
• Fluorescent probes that bind to only those parts of the chromosome with which they show a high degree of sequence similarity are used to tag sequences of DNA
• can identify a range of mutations including deletions, duplications, aneuploidy, and the presence of derivative chromosomes