Molecular Diagnostics

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Molecular Diagnostics
Molecular diagnostics is a new discipline that
captures genomic and proteomic expression
patterns and uses the information to distinguish
between normal, precancerous, and cancerous
tissues at the molecular level.
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Molecular Diagnostics
Old Way
Patients tissue sample
Pathology
Proteomics
Proteins
New Way
Mass spectrometry
Proteomic image
Genomics
Patientstissue sample or blood sample
Microarray image
DNA
Gene chip
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Gene Expression Patterns
Gene microarray
Expression pattern
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Finding Genes With Microarrays
Fluorescent cDNA
DNA
Gene chip
Scanned microarray
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Finding Genes With Microarrays (cont.)
Normal cell
Isolate mRNAs
Add to DNA microarray
Make fluorescent cDNAs
Red matches
No matches
Red matches
Scanned microarray
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Using DNA Microarrays to Measure Gene Expression
Fluorescent cDNA from muscle cell lights up
myosin gene
Myocyte
Fluorescent cDNA
Myosin mRNA
Scanned microarray
DNA microarray
reversetranscriptase
Myosin
Fluorescent cDNA from lymphocyte lights up
immunoglobulin gene
Fluorescent cDNA
ImmunoglobulinmRNA
Lymphocyte
Scanned microarray
DNA microarray
reversetranscriptase
Immunoglobulin
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Using DNA to Compare Cancer Cells to Normal Cells
Normal cell
Cancer cell
Isolate mRNAs
Make red and green fluorescent cDNAs
Add to DNA microarray
Both red and green match
Only green matches
Only red matches
No matches
Scanned microarray
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Making Sense of the Data
Cancer gene expressed 18 times more than normal
gene