C20orf94 deletion is frequently associated with TEL/AML1 positive childhood ALL and mediated by illegitimate V(D)J recombination

To gain insight into the spectrum of molecular aberrations associated with childhood leukemia we performed 100k Affymetrix SNP-array analysis in 20 ALL samples. The results were validated by high-resolution custom-made CGH array analysis. Recurrent lesions (prevalence >10%) not previously described in association with specific biological subgroups were further characterized by PCR in a large representative patient cohort. In 5 of 20 patients a deletion was seen in the 5'region of C20orf94. Deletions were stable at initial diagnosis and relapse and sequences of breakpoint junctions indicated involvement of illegi…