Fig. 9
From: Clinical significance and mechanisms associated with segmental UPD
Incomplete correction of the translocation derivative 21 in case 35. A Partial karyotype showing mosaic cell lines in case 35. Normal cell line (top panel) and derivative (21)t(12;21)(p11.22;q22.2) cell line (bottom panel, arrow). B CMA of chromosome 12 shows a mosaic terminal duplication (bracket) of 30.51 Mb in ~ 60% of cells. C CMA of chromosome 21 shows a mosaic terminal deletion (smooth signal track, bracket) of 7.12 in ~ 60% of cells. Arrow shows the initiation site of mitotic recombination at 21q21.1, resulting in replacement of the der(21) with a segment from the normal homologue and the obligate homozygotic allele dosage. D A single cell in which the der(21) initiates mitotic recombination with the normal homologue. Segregation and selection results in a second cell line with a normal copy number for chromosome 12 and 21, resulting in segUPD 21q21.1->qter