Transcript Module 1: Definitie Basiscursus Steekproeven

Example of HMMs:
copy number data
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DNA copy number is the number of copies of a genomic
segment present in the cell.
Copy numbers are measured in high-throughput fashion
using microarray techniques.
Test and reference (assumed to have copy number 2)
samples are labeled differently and hybridized together.
Under ideal circumstances, the intensity of an array
element is linearly proportional to the abundance of the
corresponding DNA sequence.
Log2 ratios of test and reference intensities reflect the
relative copy number in the test sample compared to that
in the reference sample.
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Data often modeled by HMMs.
Log2-ratio’s plotted against the
genomic order of clones.
Males have only
one copy of the
X-chromosome.
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1 2 3 4 5 6 7 8 …….
X
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Deletion on 5p
Copy
number of
each
genomic
segment
unknown.
5
After
smoothing
(de-noising)
copy
numbers still
unknown.
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