title: Aberrations of 6q13 mapped to the COL12A1 locus in chondromyxoid fibroma.
abstract: Chondromyxoid fibroma, a rare benign bone tumor, may be mistaken for chondrosarcoma. Although cytogenetic studies of chondromyxoid fibroma are few, rearrangements of the long arm of chromosome 6, frequently expressed as an inv(6)(p25q13), are prominent. In this study, conventional cytogenetic analysis of 16 chondromyxoid fibroma samples from 14 patients revealed rearrangements of chromosome 6 in 10 of 11 clonally abnormal specimens. In addition to 6q13 rearrangements, recurrent 6p25 and 6q25 anomalies were detected. Notably, an identical t(6;9)(q25;q22) translocation was identified in two cases, suggesting that it represents a distinct translocation of chondromyxoid fibroma. In an effort to further define the aberrant 6q13 breakpoint and identify the molecular consequences, a fluorescence in situ hybridization (FISH)-based positional cloning strategy on chondromyxoid fibroma abnormal metaphase and interphase cells using a series of bacterial and plasmid artificial chromosome (BAC/PAC) probe combinations spanning a 6.1 Mb region was employed. The breakpoint on 6q13 was located within the COL12A1 gene, a collagen gene purportedly involved in another benign bone tumor, subungual exostosis. The findings of this study expand our knowledge of chromosomal alterations in chondromyxoid fibroma, identify COL12A1 as the likely gene candidate within the recurrent 6q13 breakpoint, and provide an alternative approach for detecting 6q13 anomalies in nondividing cells of chondromyxoid fibroma. The latter could potentially be utilized as an adjunct in diagnostically challenging cases.
authors: Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198-3135, USA.
authors: Taketoshi
authors: T
authors: Yasuda
authors: Jun
authors: J
authors: Nishio
authors: Janos
authors: J
authors: Sumegi
authors: Kayla M
authors: KM
authors: Kapels
authors: Pamela A
authors: PA
authors: Althof
authors: Jeffrey R
authors: JR
authors: Sawyer
authors: John D
authors: JD
authors: Reith
authors: Julia A
authors: JA
authors: Bridge
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000235:genetics*; D002648:Child; D002869:Chromosome Aberrations; D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D003094:Collagen / Q000235:genetics*; D024082:Collagen Type XII; D020732:Cytogenetic Analysis; D005260:Female; D005350:Fibroma / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D008875:Middle Aged
chemical_list: C547160:COL12A1 protein, human; D024082:Collagen Type XII; D003094:Collagen