Abstract: | We report on 2 cases with different de novo unbalanced mosaic karyotypes in which each cell line had a different structural abnormality involving a common chromosome region: 46,XX,del(11)(q23.3)/46,XX,?11,+der(11)t(11;?)(q23.3;?) and 46,X,idic(Xq)/46,X,idic(Xq),?12,+der(12)t(X;12)(p11.2;p13.3). Molecular-cytogenetic analysis confirmed the origin of the derivative 12 chromosome in the latter. We present a literature review of reports with mosaic cell lines of structural chromosome abnormalities that share the same chromosome breakpoint. © 1993 Wiley-Liss, Inc. |