Human Development – Lecture 12 -- Molecular Diagnostic Tools
General:
Genome: Individual Genotype (23,000-25,000 genes)
Transcriptomics (mRNA): > 50 000 mRNAs
Proteomics (proteins): 200 000 - 400 000 protein species
Metabolomics (metabolites)
Phenotype: physiology behavior
Certain chromosomes prefer territories close to the periphery of the nucleus.
Relatively little genome expression in this region → chromosomes that contain few
active genes
Genomic DNA is tightly condensed with the aid of (non-) histones (together
named chromatin)
From DNA to protein:
Transcription (genomic DNA → mRNA)
Translation (mRNA → protein)
Genome-wide expression analysis:
Measure RNA levels of all genes expressed in the genome
Expression data provide useful information as to gene function
RNA levels vary with the following:
Type of cells
Cell or tissue development
Conditions cells are kept in
Gene expression methods:
Methods capable of giving insight into RNA expression of all genes
Can be used for diagnostic profiling
Example: cancer diagnosis
Can show how RNA levels change during development, after exposure to
stimulus, during cell cycle, etc.
Provides huge sets of data
Can help us understand how whole systems function: systems biology
Measure gene expression:
Quantifying gene expression
Elucidation of molecular events associated with a given condition
Identification of molecular markers for pathological processes
Identification of potential drug targets in pharmacogenomics
Microarray:
Expression of genes → mRNA
We either need to label this, or need to amplify this, yet there are no enzymes
that can do this!
Solution: concert the mRNA into DNA (then called copy DNA)
Label the converted mRNA; then hybridize that to a carrier containing all
genes/short pieces specific for these genes you want to analyze
Only a 100% match hybridizes
General:
Genome: Individual Genotype (23,000-25,000 genes)
Transcriptomics (mRNA): > 50 000 mRNAs
Proteomics (proteins): 200 000 - 400 000 protein species
Metabolomics (metabolites)
Phenotype: physiology behavior
Certain chromosomes prefer territories close to the periphery of the nucleus.
Relatively little genome expression in this region → chromosomes that contain few
active genes
Genomic DNA is tightly condensed with the aid of (non-) histones (together
named chromatin)
From DNA to protein:
Transcription (genomic DNA → mRNA)
Translation (mRNA → protein)
Genome-wide expression analysis:
Measure RNA levels of all genes expressed in the genome
Expression data provide useful information as to gene function
RNA levels vary with the following:
Type of cells
Cell or tissue development
Conditions cells are kept in
Gene expression methods:
Methods capable of giving insight into RNA expression of all genes
Can be used for diagnostic profiling
Example: cancer diagnosis
Can show how RNA levels change during development, after exposure to
stimulus, during cell cycle, etc.
Provides huge sets of data
Can help us understand how whole systems function: systems biology
Measure gene expression:
Quantifying gene expression
Elucidation of molecular events associated with a given condition
Identification of molecular markers for pathological processes
Identification of potential drug targets in pharmacogenomics
Microarray:
Expression of genes → mRNA
We either need to label this, or need to amplify this, yet there are no enzymes
that can do this!
Solution: concert the mRNA into DNA (then called copy DNA)
Label the converted mRNA; then hybridize that to a carrier containing all
genes/short pieces specific for these genes you want to analyze
Only a 100% match hybridizes
