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 have shown that comparative genomic hybridization microarrays fabricated with maskless array synthesizer technology can be used up to four times with application of 1,3-dimethylurea as array-stripping agent. We reproducibly detected chromosomal aberrations, 0.6 to 22.4 Mb in size, in four hybridization rounds using regenerated microarray slides. We have also demonstrated that regenerated arrays can detect smaller alterations, 16 – 200 kbp, such as common copy number variants, as well as complex aberration profiles in tumor. Peripheral blood leukocyte DNA samples from 7 individuals with subchromosomal aberrations vs a pool of female DNA (Promega). The experiments were performed in quadruplicate on succesively regenerated microarrays. One dye swap was performed..