Analysis of a 22q11.21 deletion in a proband and parents using fiber FISH. The family shown here is Family 1 in Supplemental Figure S8. Fiber FISH assemblies are aligned with a duplicon representation as defined in Figure 1. Both alleles of LCR22A and LCR22D are shown for each individual in the family trio. All individuals had the same configuration at both alleles of LCR22D, which is thus shown only once for each. (A) Parent of origin. The shared region between LCR22A and LCR22D is marked by a red box. (B) Other parent. Non-rearranged alleles of LCR22A and LCR22D transmitted to the proband are shown inside the red box. Rearranged (C) and non-rearranged (D) alleles observed in the proband. Red arrow marks duplicon(s) that were involved in recombination and define the breakpoint region.