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Staining reveals an accumulation of some DAPI-reactive material, similar to that seen in wild-type N2 nematodes but the accumulation of DNA is much less prevalent than in the wild-type strain (4-day, bottom left panel, and 14-day, bottom right panel). Fig. S2 Nuclear genome copy number quantitation using three different primer sets on three different chromo- somes results in highly correlated results. The quantified nuclear genome copy number for each individual nematode used in the study is plotted. (a) Chromosomes II vs. IV, (b) Chro- mosomes II vs. III, (c) Chromosomes IV vs. III. Fig. S3 Two additional quantitative PCR methods reveal the same trends in nuclear genome copy number for N2 and daf-2. Quantitation of nuclear genome copy number via qPCR in individual N2 (a) and daf-2 (b) nematodes. Circles = MJ 96-well plate format (and daf-2(e1368) in b). Triangles = LightCycler (and daf-2(e1370) in b). The mean copy number of genomes per animal increases with age for N2 (t test 4 vs. 24 days, P < 0.0001 MJ data set, P = 0.0013 LightCycler data set). The mean copy number also increases for daf-2 between 4 and 19 days of age (P = 0.04 4 vs. 19 days, LightCycler data set, P = 0.001 MJ data set), and then falls with age (P < 0.0001 19 vs. 59 days, LightCycler data for daf-2(e1370), P = 0.056 14 vs. 34 days, MJ data for daf- 2(e1368)). See sup- plemental methods. Fig. S4 The germline deficient mutant glp-4 does not have a wild-type nuclear genome content, even at the permissive temperature. The number of copies of the nuclear genome, as assayed by qPCR, for individual N2 or glp-4 nematodes at either 25 °C or 17 °C are shown. Each dot represents a single worm, and 15 individuals were assayed per condition.