Novel chimera in tumorous bone lesion carrying a t(4;11;14;12)(q35;p15;q22;q13).

BACKGROUND

Benign fibro-osseous lesions are characterized by the replacement of normal bone with cellular fibrous connective tissue with new bone formation. The published cytogenetic information on these tumors is limited to only few cases. Here, we report the cytogenetic and molecular genetic findings of a fibro-osseous tumor.

METHODS

A fibro-osseous lesion was investigated for genetic abnormalities using banding cytogenetics, fluorescence hybridization (FISH), RNA sequencing, and direct cycle Sanger sequencing.

RESULTS

The karyotype was 46,XX,t(4;11;14;12)(q35;p15;q22;q13)[7]/46,XX [3], with no rearrangement of . RNA sequencing revealed two chimeric transcripts, originating from the fusion point 14q22;11p15 of the t(4;11;14;12). In these transcripts, exon 1 of fused to either exon 1 or exon 2 of . Direct cycle sequencing confirmed the presence of these chimeric transcripts.

CONCLUSION

This study reports, for the first time, the presence of the chimera in fibro-osseous tumor. In this chimera the expression of the entire coding region of is regulated by the ubiquitously expressed gene promoter. Dysregulation of expression may have significant implications for processes regulated by PTH protein.