Fig. 3
From: Mechanisms of structural chromosomal rearrangement formation
Non-Allelic Homologous Recombination (NAHR) mechanism. A NAHR leading to the formation of duplication and deletion: (a) Normal chromosome pairing and alignment of Low Copy Repeats (LCRs) in the same orientation. (b) A misalignment between LCRs due to their high level of sequence identity leads to an unequal crossing over event that can generate (c) a duplication and (d) a deletion. The scheme represents the LCRs of region 22q11.2. NAHR between LCR-A and LCR-B leads to a deletion seen in 8% of the cases of 22q11.2 deletion syndrome. B NAHR leading to the formation of inversions: (a) Normal chromosome pairing and alignment of Low Copy Repeats (LCRs). LCR-X and LCR-Z present similar DNA sequences but in opposite orientations. (b) A misalignment between LCRs due to their high level of sequence identity leads to an unequal crossing over event that can generate (c) an inversion