Article

Constitutional tandem duplication of 9q34 that truncates EHMT1 in a child with ganglioglioma

Texas Children's Cancer Center, Baylor College of Medicine, Houston, Texas, USA.
Pediatric Blood & Cancer (Impact Factor: 2.56). 05/2012; 58(5):801-5. DOI: 10.1002/pbc.23219
Source: PubMed

ABSTRACT Point mutations of EHMT1 or deletions and duplications of chromosome 9q34.3 are found in patients with variable neurologic and developmental disorders. Here, we present a child with congenital cataract, developmental and speech delay who developed a metastatic ganglioglioma with progression to anaplastic astrocytoma. Molecular analysis identified a novel constitutional tandem duplication in 9q34.3 with breakpoints in intron 1 of TRAF2 and intron 16 of EHMT1 generating a fusion transcript predicted to encode a truncated form of EHMT1. The ganglioglioma showed complex chromosomal aberrations with further duplication of the dup9q34. Thus, this unique tandem 9q34.3 duplication may impact brain tumor formation.

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