Regeneration of comparative genomic hybridization oligonucleotide microarrays with dimethylurea

Reuse of materials in DNA hybridization-based methods has been known since the advent of Southern membranes. Array-based comparative genomic hybridization is essentially Southern hybridization with multiple probes immobilized on a solid surface. We show that comparative genomic hybridization microarrays fabricated with maskless array synthesizer technology can be used up to four times with the application of 1,3-dimethylurea as an array-stripping agent. We reproducibly detected chromosomal aberrations (0.6-22.4Mb in size) in four hybridization rounds using regenerated microarray slides. We also demonstrated that regenerated arrays can detect smaller alterations (16-200kbp), such as common copy number variants, as well as complex aberration profiles in tumor DNA.