Gain and/or amplification of chromosome 1q are frequently found in Multiple Myeloma (MM).

Background: Gain and/or amplification of chromosome 1q are frequently found in Multiple Myeloma (MM). The number of 1q copies correlates with a poor prognosis. The aim of this work is to study the impact on the clinical outcome and the trascriptomic changes induced by Gain1q (3 copies of 1q, 3X) and amplification 1q (Amp1q, ≥4 copies of 1q, 4X) in MM patients enrolled in the CoMMpass study (NCT145429). Methods: Fluorescence in situ hybridization (FISH) in CD138+ purified bone marrow plasma cells was centralized and performed at baseline. The cut-off level for Gain1q was 10% of nuclei with ≥3 copies of 1q (3X), while Amp1q was defined as ≥ 20% of nuclei with ≥4 copies of 1q (4X). Transcriptome data from patients were used to find differentially expressed genes (DEGs) in gain (3X) and amp1q (4X) patients. 24 samples, 8 with two copies of 1q (2X), 8 with three copies of 1q (3X) and 8 with four copies of 1q (4X)