Deciphering the Complexities of MECOM Rearrangement-Driven Chromosomal Aberrations

This study presented 129 cases with confirmed MECOM rearrangement by karyotyping and multiple FISH methodologies. MECOM rearrangement arose through translocation (49.6%, n=64), inversion (40.3%, n=52), insertion (5.4%, n=7) or unknown mechanism(s) (4.7%, n=6). The classic inv(3)(q21q26.2) was dominant (n=50) in inversion-driven MECOM rearrangement; and 3 of them also had double inv(3). For translocation-driven MECOM rearrangement, t(3;21) was most common (n=15), followed by t(2;3) (n=13), t(3;12) (n=10), t(3;3) (n=9), t(3;8) (n=6), t(3;6) and t(3;17) (n=4 each), t(1;3) and t(3;?) (n=1 each). Cases with t(3;3)-, t(3;12)-, and insertion-driven MECOM rearrangement were prone to exhibit a complex karyotype, while cases with t(2;3)-, t(3;21)- and insertion-driven MECOM rearrangement were prone to have an “unbalanced” MECOM FISH signal pattern, likely caused by uncommon breakpoint(s) within the target of 5’MECOM probe. Therefore, atypical chromosomal aberrations and/or mechanisms are involved in MECOM rearrangement. Confirmation/exclusion of MECOM rearrangement is necessary in all cases with a 3q26.2 abnormality. (Word count: 190)
Source: Cancer Genetics - Category: Cancer & Oncology Source Type: research