Alteration of cohesin genes in myeloid diseases.

New genes involved in leukemogenesis, such as ASXL1 and TET2, have been identified recently using genomic analyses of DNA from patient samples. We have studied by array-comparative genomic hybridization (aCGH) a series of 167 samples including myelodysplastic syndromes, chronic myelomonocytic leukemias, and acute myeloid leukemias. We found a deletion of the RAD21 and STAG2 genes, which encode two components of the cohesin complex. We propose that these alterations may compromise the cohesin complex and its regulation of the transcription of genes.