Genomic technologies have emerged as an extremely useful tools in cancer research. International projects such as the International Cancer Genome Consortium and The Cancer Genome Atlas, tasked with mapping the biological science of dozens of tumor types, would not have been possible without these tools. Next-generation sequencing (NGS) and high-density microarrays are used to study cancer biology. Both provide the cancer research community with a growing body of information that may lead to more effective medicine, better patient treatment options, and more accurate prognoses.
NGS is suited to the study of cancer biology.
- Paired tumor-normal (T/N) whole-genome sequencing (WGS) or T/N whole-exome sequencing (WES) have emerged as ideal methods for the discovery of somatic mutations.
- NGS-based RNA sequencing (RNA-Seq) has revolutionized gene expression studies by enabling researchers to measure relative expression changes across the whole genome in a single experiment and to identify novel transcripts.
- RNA-Seq has emerged as a leading method for identifying gene fusions, a critical class of somatic driver mutations in tumor cells.
- Chromatin immunoprecipitation sequencing (ChIP-Seq), bisulfite sequencing, or methylation-targeting microarrays, can be used to investigate the role of epigenetic factors in the biology of tumorigenesis.
The adoption of these genomic approaches in cancer research has led to a deeper understanding of tumor biology and is establishing the foundation necessary to support the long-term goals of personalized medicine. Researchers are also using NGS and microarray-based genotyping of germline DNA to identify inherited variations that influence cancer susceptibility. While NGS is an excellent tool for assessing the germline status of known cancer predisposition genes and identifying novel loci, microarrays are ideal for large-scale population studies, where large sample numbers are required to identify weakly predisposing genes. This primer describes the broad portfolio of genomic technologies offered by Illumina that are directly applicable to cancer research.
Terms to remember:
next-generation sequencing – refers to large-scale DNA sequencing technology that allows for querying the entire genome (whole genome), the exons within all known genes (whole exome), or only exons of selected genes (target panel)
exome sequencing – is a genomic technique for sequencing all of the protein-coding regions of genes in a genome (known as the exome)
RNA-seq – is a particular technology-based sequencing technique which uses next generation sequencing (NGS) to reveal the presence and quantity of RNA in a biological sample at a given moment, analyzing the continuously changing cellular transcriptome
chromatin immunoprecipitation (ChIP) – is a method used to determine the location of DNA binding sites on the genome for a particular protein of interest
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