The recently released Infinium HumanMethylation450 array (the 450k array) provides a high-throughput assay to quantify DNA methylation (DNAm) at xe2x88xbc450 000 loci across a range of genomic features. Although less comprehensive than high-throughput sequencing-based techniques, this product is more cost-effective and promises to be the most widely used DNAm high-throughput measurement technology over the next several years.