Chromothripsis Is a Recurrent Genomic Abnormality in High-Risk Myelodysplastic Syndromes

PLoS One. 2016 Oct 14;11(10):e0164370. doi: 10.1371/journal.pone.0164370. eCollection 2016.

Abstract

To explore novel genetic abnormalities occurring in myelodysplastic syndromes (MDS) through an integrative study combining array-based comparative genomic hybridization (aCGH) and next-generation sequencing (NGS) in a series of MDS and MDS/myeloproliferative neoplasms (MPN) patients. 301 patients diagnosed with MDS (n = 240) or MDS/MPN (n = 61) were studied at the time of diagnosis. A genome-wide analysis of DNA copy number abnormalities was performed. In addition, a mutational analysis of DNMT3A, TET2, RUNX1, TP53 and BCOR genes was performed by NGS in selected cases. 285 abnormalities were identified in 71 patients (23.6%). Three high-risk MDS cases (1.2%) displayed chromothripsis involving exclusively chromosome 13 and affecting some cancer genes: FLT3, BRCA2 and RB1. All three cases carried TP53 mutations as revealed by NGS. Moreover, in the whole series, the integrative analysis of aCGH and NGS enabled the identification of cryptic recurrent deletions in 2p23.3 (DNMT3A; n = 2.8%), 4q24 (TET2; n = 10%) 17p13 (TP53; n = 8.5%), 21q22 (RUNX1; n = 7%), and Xp11.4 (BCOR; n = 2.8%), while mutations in the non-deleted allele where found only in DNMT3A (n = 1), TET2 (n = 3), and TP53 (n = 4). These cryptic abnormalities were detected mainly in patients with normal (45%) or non-informative (15%) karyotype by conventional cytogenetics, except for those with TP53 deletion and mutation (15%), which had a complex karyotype. In addition to well-known copy number defects, the presence of chromothripsis involving chromosome 13 was a novel recurrent change in high-risk MDS patients. Array CGH analysis revealed the presence of cryptic abnormalities in genomic regions where MDS-related genes, such as TET2, DNMT3A, RUNX1 and BCOR, are located.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Child
  • Chromosome Aberrations*
  • Chromosomes, Human, Pair 13
  • Comparative Genomic Hybridization
  • Core Binding Factor Alpha 2 Subunit / genetics
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA / chemistry
  • DNA / isolation & purification
  • DNA / metabolism
  • DNA Copy Number Variations
  • DNA Methyltransferase 3A
  • DNA Mutational Analysis
  • DNA-Binding Proteins / genetics
  • Dioxygenases
  • Female
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Karyotype
  • Male
  • Middle Aged
  • Myelodysplastic Syndromes / diagnosis
  • Myelodysplastic Syndromes / genetics*
  • Myelodysplastic Syndromes / pathology
  • Proto-Oncogene Proteins / genetics
  • Recurrence
  • Risk
  • Tumor Suppressor Protein p53 / genetics
  • Young Adult

Substances

  • Core Binding Factor Alpha 2 Subunit
  • DNA-Binding Proteins
  • DNMT3A protein, human
  • Proto-Oncogene Proteins
  • RUNX1 protein, human
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • DNA
  • Dioxygenases
  • TET2 protein, human
  • DNA (Cytosine-5-)-Methyltransferases
  • DNA Methyltransferase 3A