Illumina

Methylation

There are two product options for methylation analysis: GoldenGate and Infinium.

GoldenGate Methylation

 

Using GoldenGate Assay technology, oligonucleotide primers query putative methylation sites in bisulfite-converted genomic DNA. Bisulfite treatment of unmethylated CpG converts cytosine to uracil, while methylated cytosines are protected from conversion. Similar to methylation-specific PCR, two primer sets are designed for each CpG target; one primer set corresponds to the unmethylated, bisulfite-converted sequence (uracil) while the other corresponds to the unconverted sequence (5-methyl cytosine). The extent of methylation at a given CpG site is determined by comparing the proportion of signal from methylated and unmethylated alleles in the DNA sample. Enzymatic discrimination takes place on the single nucleotide level with additional inferred methylation information for adjacent CpG sites that fall within the assay probe target region.

Further information can be found here.

Infinium Methylation

Powered by Illumina’s revolutionary Infinium Assay, the HumanMethylation27 DNA Analysis BeadChip allows researchers to interrogate 27,578 highly informative CpG sites per sample at single-nucleotide resolution. This 12-sample BeadChip features content derived from the well-annotated NCBI CCDS database (Genome Build 36) and is supplemented with more than 1,000 cancer-related genes described in published literature. Probe content has been enriched to deeply cover more than 150 well-established cancer genes known to show differential methylation patterns. HumanMethylation27 BeadChip content also targets the promoter regions of 110 miRNA genes.

Further information can be found here.