LCR22s mediate deletions/duplications and translocations. The line spanning left to right, represents the q11 region of chromosome 22 (cen indicates centromere). The LCR22s mediate the 22q11.2 deletion syndrome (velo-cardio-facial/DiGeorge syndrome), the reciprocal duplication syndrome, as well as the known recurrent t(11;22) translocation and t(17;22) translocation. LCR22-2 and -4 are >99% identical and through homologous recombination mediate the deletion syndromes, as well as, the duplication disorders. LCR22-3a is involved in the deletion syndromes as well but is predominately involved in translocations.