Multiplex ligation-dependent probe amplification and fluorescence in situ hybridization for detecting chromosome abnormalities in myelodysplastic syndromes: A retrospective study

This study aimed to compare interphase fluorescence in situ hybridization (iFISH) and multiplex ligation dependent probe amplification (MLPA) for identifying genetic changes in myelodysplastic syndromes (MDS). The frequencies of cytogenetic changes in MDS patients treated at the Institute of Hematology and Blood Disease Hospital (China) in 2009 to 2018 were assessed by iFISH based on bone marrow samples. Then, the effectiveness of MLPA in detecting these anomalies was evaluated. Specimens from 287 MDS patients were assessed. A total of 36.9% (103/279) of MDS cases had chromosomal abnormalities detected by iFISH; meanwhile, 44.1% (123/279) harbored ≥1 copy-number variation (CNV) based on MLPA: +8 (n=46), −5 (n = 39), −7 (n = 27), del 20 (n = 32) and del 17 (n = 17). Overall, 0 to 4 aberrations/case were detected by MLPA, suggesting the heterogeneous and complex nature of MDS cytogenetics. There were 29 cases detected by MLPA, which were undetected by FISH or showed low signals. Sixteen of these cases had their risk classification changed due to MLPA detection, including 9 reassigned to the high-risk IPSS-R group. These findings demonstrated that MLPA is highly efficient in assessing cytogenetic anomalies, with data remarkably corroborating FISH findings (overall consistency of 97.1%). The sensitivities of MLPA in detecting +8, −5, −7, del 20 and del 17 were 92.3%, 97.1%, 100%, 100%, and 90%, respectively, with specificities of 95.8%, 97.6%, 97.7%, 97.6%, and 97%, respectively. MLPA represents a reliable approach, with greater efficiency, accuracy, and speed than iFISH in identifying cytogenetic aberrations in MDS.