This web page was produced as an assignment for a course on
Statistical Analysis on Microarray Data at
Description of the experiment for “MicroRNA Expression Signature of Human Sarcomas”
BACKGROUND
MicroRNAs (miRNAs) are ~20 nucleotide long non-coding RNAs. Evidence suggests that miRNAs act as tumor suppressors or oncogenes (a gene with DNA sequence that causes cancer) that control cell growth and death.
GOAL
The researchers believe that there is a correlation between miRNA expression patterns and known sarcomas (cancer of connective or supportive tissue such as bone, cartilage, fat, muscle, or blood vessels and soft tissues).
RESULTS
The study found clustering of miRNA expressions in the different types of cancer. During the research, two of the samples were found in unexpected clusters and the researchers discovered that these cases had been misdiagnosed originally.
TIME FRAME of experiment
The microarray data was collected between November 2006 and July 2007.
PROBLEMS with the experiment
Slides that have problems:
(If the links do not work correctly, go here and select “display data” and then the links below should work).
76169 – red blotch
71656 – red noise in background
71057 – lots of noise in background
71074 – lots of noise in background
*71062 – lots of red noise in background
71823 – red blotch
71063 – noisy background
71061 – bright non-uniform background
71072 – blotchy and noisy background
71655 – red noise in background
*71073 – only green and yellow, no red
*71056 – lots of bright red noise in background
*71814 – background nearly saturated red
71808 – red noise in background
71815 – red noise in background
*71813 – lots of red noise in background
71824 – red noise in background
*71817 – all green and yellow except background red noise
*71068 – bright red background
*particularly bad
Out of 34 microarrays, 19 stood out as being not very clean, and 7 stood out as being exceptionally poor. There does not seem to be any problems in the article itself.
This website was designed by Austen Head.
Email: austen
[dot] head [at]