Wikipages

Question 0

cDNA microarrays:

1) what is the first step. Why is cDNA used rather than mRNA? What is used as a reference?
2) what reagents are added?
3) what are these samples hybridised on?
4) what are bound labels detected with?

Answer 0

1) produce complementary cDNA from mRNA isolated from specific tissue samples. mRNA used as it is more stable. Normal tissue as reference.
2) primers, reverse transcriptase and dNTPs, followed by the fluorescent tags
3) microarray plate
4) high resolution laser scanner

Question 1

What are microarrays? What information are cDNA microarrays used to obtain?

Answer 1

Technique used to screen biological material by tagging material with a fluorescent label, and quantifying the amount of DNA present.
Commonly used to obtain genetic information about diseases and cancer.

Question 2

Give some advantages and disadvantages of cDNA microarrays?

Answer 2

Advantages : can measure expression of a large number of genes
Can genotype multiple genome regions
Fast process
Array can contain thousands of probes so that many tests can be run together

Disadvantages:
No standardised way to share results (results relative to individual and tissue)
Data collected from different platforms cannot be compared
Costly
Quality of the microarrays cannot be sufficiently tested to ensure they are fully functional
Background noise can affect results