In this journal, Mestichelli et al (2018) recently reported that a submicroscopic 22q11 deletion is a potentially significant genomic aberration in chronic lymphocytic leukaemia (CLL), and that this alteration is missed by current routine techniques. This was based on the analysis of 23 CLL cases by oligonucleotide-based array comparative genomic hybridisation (aCGH; CytoChipCancer 4x180K, Illumina). The authors found 4 CLL cases with a deletion located at 22q11 that ranged in size from 0.68 Mb–0.49 Mb. The authors claimed that the minimally deleted region included the ZNF280A, ZNF280B, GGTLC2 and PRAME genes. The deletion in the 22q11 region was originally described by Gunn et al (2009) using aCGH and detected in 28 out of 187 analysed CLL cases.