Potential outcomes of interchromosomal NAHR mediated by LCRs. Nonhomologous chromosomes are shown in black and white with the centromeres shown as circles. The arrows indicate the orientation of the LCRs. Only interchromosomal LCRs located in the same orientation on the same chromosomal arms (i.e., q-arm to q-arm) (A), or those in opposite orientation on different chromosomal arms (i.e., q-arm to p-arm) (C) are predicted to result in stable, monocentric reciprocal translocations. In contrast, LCRs located on the same chromosomal arm in opposite orientation (B) or on different chromosomal arms in the same orientation (D) would lead to unstable dicentric or acentric chromosomes, resulting in chromosome breakage or loss, respectively. Note: Both HR substrate orientation (direct versus inverted) and chromosomal arm location (p versus q), required for viable interchromosomal recombinant products.
