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Affymetrix SNP array data for xenografted transient abnormal myelopoiesis samples

ABSTRACT: Transient abnormal myelopoiesis (TAM) is a clonal pre-leukemic disorder that progresses to myeloid leukemia of Down syndrome (ML-DS) through the accumulation of genetic alterations. To investigate the mechanism of leukemogenesis in this disorder, a xenograft model of TAM was established using NOD/Shi-scid, IL-2Rγnull mice. In serial transplantations, engrafted TAM-derived cells showed the emergence of divergent subclones with another GATA1 mutation and various CNAs, including a 16q deletion and 1q gain, which are clinically associated with ML-DS. These results suggest that genetically heterogeneous subclones with varying leukemia-initiating potential already exist in the neonatal TAM phase, and ML-DS may develop from a pool of such minor clones through clonal selection.

ORGANISM(S): Homo sapiens

PROVIDER: GSE44739 | GEO | 2013/03/01

SECONDARY ACCESSION(S): PRJNA191153

REPOSITORIES: GEO

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Affymetrix SNP array data for xenografted transient abnormal myelopoiesis samples

Project description:Transient abnormal myelopoiesis (TAM) is a clonal pre-leukemic disorder that progresses to myeloid leukemia of Down syndrome (ML-DS) through the accumulation of genetic alterations. To investigate the mechanism of leukemogenesis in this disorder, a xenograft model of TAM was established using NOD/Shi-scid, IL-2Rγnull mice. In serial transplantations, engrafted TAM-derived cells showed the emergence of divergent subclones with another GATA1 mutation and various CNAs, including a 16q deletion and 1q gain, which are clinically associated with ML-DS. These results suggest that genetically heterogeneous subclones with varying leukemia-initiating potential already exist in the neonatal TAM phase, and ML-DS may develop from a pool of such minor clones through clonal selection. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from murine bone marrow (hCD45 sorted) or human peripheral blood samples. Copy number analysis of Affymetrix 500K SNP arrays was performed for xenografted TAM samples of 3 patients. There are also 3 samples from TAM patients in remission, which were used as references for copy number inference.

2013-03-01 | E-GEOD-44739 | biostudies-arrayexpress

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