Microarrays
- Enables parallel analysis of thousands of genes or genetic elements on a single platform.
- Measures mRNA levels by fluorescent labeling and hybridization to DNA probes to profile gene expression.
- Detects specific nucleotides at SNP positions by hybridizing DNA samples to SNP-specific probes for genotyping.
Definition
Section titled “Definition”Microarrays are a type of technology used in molecular biology that allows for the simultaneous analysis of thousands of genes or other genetic elements.
Explanation
Section titled “Explanation”Microarrays permit large-scale interrogation of genetic material by presenting thousands of probes on a solid support. For gene expression profiling, mRNA is labeled with fluorescent probes and hybridized to a microarray containing thousands of DNA probes complementary to the mRNA; the array is scanned and fluorescence levels for each probe are measured to identify differentially expressed genes. For SNP genotyping, DNA from an individual is hybridized to a microarray containing probes for each SNP of interest; the array is scanned and probe-specific fluorescence measurements indicate the nucleotide present at each SNP position. This technology has been applied to gene expression profiling, SNP genotyping, and genome-wide association studies.
Examples
Section titled “Examples”Gene expression profiling
Section titled “Gene expression profiling”Gene expression profiling measures the levels of mRNA (transcriptional activity) in a sample. Typically, the mRNA is labeled with fluorescent probes and hybridized to a microarray containing thousands of DNA probes complementary to the mRNA. The microarray is scanned and the levels of fluorescence for each probe are measured, allowing for the identification of differentially expressed genes. This information can be used to study the regulation of gene expression in response to different stimuli or conditions, and has been used to identify potential drug targets and biomarkers.
SNP genotyping
Section titled “SNP genotyping”SNP genotyping determines the specific nucleotide at a particular position in the genome. This is typically done by hybridizing a sample containing DNA from an individual to a microarray containing probes for each SNP of interest. The microarray is then scanned and the levels of fluorescence for each probe are measured, allowing for the identification of the specific nucleotide at each SNP position. This information can be used in genetic association studies to identify genetic variations associated with diseases or other traits.
Use cases
Section titled “Use cases”- Gene expression profiling
- SNP genotyping
- Genome-wide association studies
Related terms
Section titled “Related terms”- Gene expression profiling
- SNP genotyping
- Genome-wide association studies