Figure 9.

(i), Tandem duplication of DAZ genes in NBR-exposed males uncovered by FISH. Numbers in parentheses represent copies of DAZ genes ranging from 4–16 in the exposed males with corresponding variation in signal intensity. Sample IDs are given in square brackets. Note three signals in samples 3F, 24F and 13F, with two on one side and a single one on the other, highlighting the unilocus duplication of DAZ genes (see text for details). (ii), Organization of DAZ genes in exposed males. Only six representative exposed males and a normal one (Nm) are shown, with their sample IDs on top, copies of DAZ in parentheses, and probes on the right of the panels. The normal male (Nm) showed the expected number of discernible signals for each probe (A–E) with combinations of AtrBfl and AtrCfl separating two signals. Exposed males showed higher DAZ copies corresponding to unilocus (RE53F & RE53B) or bilocus duplications (RE52F, RE54F, RE54B, & RE56F) evident from the number and intensity of the corresponding signals shown in (A), (B) and (D), respectively. Similarly, probe “D” specific for green amplicons showed three expected signals overlapping “B” with “C” in normal males. In exposed males, 80–90% of cells showed unexpected overlap of probe “D” signal with that of “A” (RE53F, 54F & 56F), as shown in (C). Presence of three signals with probe D was confirmed by different probe combinations as shown in (D) and (E). (F) Schematic map of the AZFc amplicons given as a reference.