Fig. 2
From: Clinical significance and mechanisms associated with segmental UPD
Graphic depiction of mitotic-mediated correction of meiotically derived imbalance. Double-strand break mediated repair results in inter-homologue recombination during S phase of a diploid chromatid (pink) with a chromatid (blue) containing a terminal rearrangement (orange). This results in two chromosome homologues, each containing one recombinant chromatid. Subsequent mitotic segregation can result in two outcomes: two daughter cells that, like the parent cell, are heterozygous for the original imbalance or in the outcome described in the figure. In this case one daughter cell is homozygous for the imbalance and the other is euploid but with uniparental inheritance in the recombinant region, segUPD, detected as a terminal ROH in microarray testing. Survival and expansion are more likely for the euploid daughter cell. However, variable selective pressure, both in cancer and some constitutional alterations, can result in clonal expansion of cells with the imbalance post mitotic recombination