Interphase nuclei of individuals with a structurally abnormal chromosome 22 showing a double (ds) and a single signal (ss) for probes within the commonly deleted 22q11.2 region and at flanking positions
| Case, gender* | Chromosomes 22 (denoted A and B) | FISH probes† | Derivative chromosomes on which the 22q probes hybridise (chromosomes “A”) | Interphase nuclei showing ds/ss for single probes§ or 2×ds on one chr. 22 and 2×ss on the other chr. 22 for combinations of two probes¶ | Interpretation and comments | ||
|---|---|---|---|---|---|---|---|
| ds on A | ds on B | Total‡ | |||||
| *M, male; F, female; †The relative location of the probes is as follows: “D22S427”: proximal to the LCRI; LSI DiGeorge/VCFS: within the deleted region, proximal to the breakpoint of the t(11;22); ZNF74: within the commonly deleted region, distal to the breakpoint of the t(11;22); “D22S936”: within the commonly deleted region, proximal to the LCRII (8,17); ARSA: distal to the LCRII, 22q13.3; ‡In brackets: total number of interphase nuclei analysed; §The cells with ds/ss, ds/ds and ss/ss were scored, but only the percentage with ds/ss is indicated, being the value of relevance in this context; ¶Out of the 16 possible combinations of ds and ss for two probes on the two chromosomes 22, the combination ds/ds on one chromosome 22 and ss/ss on the other chromosome 22 is indicated being the most frequently detected combination in most cases (additional data are indicated in cases 34–36 where another combination was more frequent). | |||||||
| 31, F | A: t(6;22)(q26;q11.2) mat; B: structurally normal | LSI DiGeorge/VCFS ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 6 | 24% 24% 19% | 59% 55% 49% | 83% (122) 79% (122) 68% | Non-random asynchronous replication: paternal chromosome 22 early replicating |
| 32, F | A: t(11;22)(q23;q11.2); B: structurally normal | “D22S427” LSI DiGeorge/VCFS | der 22 der 22 | 4% 26% | 69% 63% | 73% (307) 89% (102) | Non-random asynchronous replication |
| ZNF74 | der 11 | 6% | 47% | 53% (115) | |||
| “D22S936” | der 11 | 0 | 62% | 62% (107) | |||
| ARSA | der 11 | 5% | 65% | 70% (169) | |||
| “D22S427” and ZNF74 | 2% | 45% | 47% (105) | ||||
| “D22S427” and “D22S936” | 0 | 52% | 52% (107) | ||||
| “D22S427” and ARSA | 0 | 61% | 61% (88) | ||||
| LSI DiGeorge/VCFS and ARSA | 0 | 63% | 63% (81) | ||||
| 33, F | A: t(11;22)(q23;q11.2); B: structurally normal | LSI DiGeorge/VCFS ARSA | der 22 der 11 | 24% 24% | 69% 65% | 93% (98) 89% (93) | Non-random asynchronous replication |
| LSI DiGeorge/VCFS and ARSA | 22% | 64% | 86% (93) | ||||
| 34, M | A: t(11;22)(q23;q11.2) pat; B: structurally normal | LSI DiGeorge/VCFS ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 11 | 48% 21% 10% (52% A: ds-ss; B: ss-ss) | 18% 19% 0 | 66% (152) 40% (102) 10% (102) | Non-random asynchronous replication: paternal chromosome 22 early replicating |
| 35, M | First son of case 34; A: t(11;22)(q23;q11.2) pat; B: structurally normal | “D22S427” LSI DiGeorge/VCFS ZNF74 “D22S936” ARSA “D22S427” and ZNF74 “D22S427” and “D22S936” “D22S427” and ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 22 der 11 der 11 der 11 | 59% 61% 10% 3% 14% 2% 2% 3% 11% (63% A: ds-ss; B: ss-ss) | 11% 20% 17% 6% 13% 3% 3% 2% 0 | 70% (316) 81% (123) 27% (109) 9% (104) 27% (210) 5% (106) 5% (104) 5% (103) 11% (107) | Non-random asynchronous replication for the probes proximal to the translocation breakpoint: paternal chromosome 22 early replicating; Segment of chromosome 22 distal to the translocation breakpoint no longer asynchronous replicating |
| 36, M | Second son of case 34; A: t(11;22)(q23;q11.2) pat; B: structurally normal | LSI DiGeorge/VCFS ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 11 | 50% 10% 10% (55% A: ds-ss; B: ss-ss) | 32% 30% 0 | 82% (135) 40% (100) 10% (100) | Non-random asynchronous replication: paternal chromosome 22 early replicating |
| 37, F | A: t(19;22)(p13.3;q11.2); B: structurally normal | LSI DiGeorge/VCFS ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 19 | 26% 29% 25% | 62% 56% 50% | 88% (100) 85% (100) 75% (100) | Non-random asynchronous replication |
| 38, F | Daughter of case 37; A: t(19;22)(p13.3;q11.2); B: structurally normal | LSI DiGeorge/VCFS ARSA LSI DiGeorge/VCFS and ARSA | der 22 der 19 | 29% 28% 24% | 60% 61% 53% | 89% (100) 89% (100) 77% (100) | Non-random asynchronous replication: paternal chromosome 22 early replicating |
| 13, F | A: maternal 22q11.2 deletion; B: structurally normal | “D22S427” ARSA “D22S427” and ARSA” | der 22 der 22 | 3% 6% 2% | 66% 62% 51% | 69% (117) 68% (117) 53% (117) | Non-random asynchronous replication: paternal chromosome 22 early replicating |
| 17, F | A: paternal 22q11.2 deletion; B: structurally normal | “D22S427” ARSA “D22S427” and ARSA” | der 22 der 22 | 65% 60% 50% | 2% 8% 1% | 67% (78) 68% (78) 51% (78) | Non-random asynchronous replication: paternal chromosome 22 early replicating |