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SNP array-based karyotyping: differences and similarities between aplastic anemia and hypocellular myelodysplastic syndromes.

ABSTRACT: In aplastic anemia (AA), contraction of the stem cell pool may result in oligoclonality, while in myelodysplastic syndromes (MDS) a single hematopoietic clone often characterized by chromosomal aberrations expands and outcompetes normal stem cells. We analyzed patients with AA (N = 93) and hypocellular MDS (hMDS, N = 24) using single nucleotide polymorphism arrays (SNP-A) complementing routine cytogenetics. We hypothesized that clinically important cryptic clonal aberrations may exist in some patients with BM failure. Combined metaphase and SNP-A karyotyping improved detection of chromosomal lesions: 19% and 54% of AA and hMDS cases harbored clonal abnormalities including copy-neutral loss of heterozygosity (UPD, 7%). Remarkably, lesions involving the HLA locus suggestive of clonal immune escape were found in 3 of 93 patients with AA. In hMDS, additional clonal lesions were detected in 5 (36%) of 14 patients with normal/noninformative routine cytogenetics. In a subset of AA patients studied at presentation, persistent chromosomal genomic lesions were found in 10 of 33, suggesting that the initial diagnosis may have been hMDS. Similarly, using SNP-A, earlier clonal evolution was found in 4 of 7 AA patients followed serially. In sum, our results indicate that SNP-A identify cryptic clonal genomic aberrations in AA and hMDS leading to improved distinction of these disease entities.

SUBMITTER: Afable MG

PROVIDER: S-EPMC3128479 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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SNP array-based karyotyping: differences and similarities between aplastic anemia and hypocellular myelodysplastic syndromes.

Afable Manuel G MG Wlodarski Marcin M Makishima Hideki H Shaik Mohammed M Sekeres Mikkael A MA Tiu Ramon V RV Kalaycio Matt M O'Keefe Christine L CL Maciejewski Jaroslaw P JP

Blood 20110428 25

In aplastic anemia (AA), contraction of the stem cell pool may result in oligoclonality, while in myelodysplastic syndromes (MDS) a single hematopoietic clone often characterized by chromosomal aberrations expands and outcompetes normal stem cells. We analyzed patients with AA (N = 93) and hypocellular MDS (hMDS, N = 24) using single nucleotide polymorphism arrays (SNP-A) complementing routine cytogenetics. We hypothesized that clinically important cryptic clonal aberrations may exist in some pa ...[more]

PMID: 21527527

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Dataset Information

SNP array-based karyotyping: differences and similarities between aplastic anemia and hypocellular myelodysplastic syndromes.

Publications

SNP array-based karyotyping: differences and similarities between aplastic anemia and hypocellular myelodysplastic syndromes.

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