Illumina HumanGW-6 v2.0 BeadChip: The Human-6 v2 beadchip simultaneously assays six samples, therefore, known as ‘array of arrays’. Each chip has ~1.8 million beads, beads have several hundred thousands copies of optimized 50-mer gene-specific probes. These probes cover more than 48,000 transcripts per sample, targeting genes and known alternative splice variants from the RefSeq database release 17 and UniGene build 188.