Distribution and suppression of repeat sequences. a) Distribution (in 5% bins) and frequency of repeat sequences within probes on the array. b). Suppression of repeat-specific signal using Cot1 DNA. Two independent hybridizations were carried out using genomic DNA extracted from CD8+ lymphocytes. In both experiments total DNA was labelled with Cy5 dye. Only in one of them unlabelled Cot1 DNA was added. In the non-Cot1 hybridization, Cy5 intensity increases almost linearly with repeat density until it reaches a plateau (around 25,000 Cy5 intensity). In the presence of Cot1 DNA, Cy5 intensity of highly repetitive probes is comparable to those of repeat-free probes. Repeats were defined based on the 'All repeats' track in Ensembl browser .