Figure 6

Problems of I-FISH with centromeric/site-specific DNA probes. (A) and (B) replication of specific genomic loci (LSI21 probe) -- some nuclei exhibit replicated signals, whereas in some nuclei it is not apparent; note the distance between signals can be more than a diameter of a signal; (C) asynchronous replication of a signal (DXZ1) in case of tetrasomy of chromosome X; note the difficulty to make a definitive conclusion about number of signals in the right nucleus; (D) Two-color FISH with centromeric/site-specific DNA probes for chromosome 1 shows chromosomal associations in a nucleus isolated from the adult human brain; note the impossibility to identify number of chromosomes; (E) QFISH demonstrating an association of centromeric regions of homologous chromosomes 9, but not a monosomy or chromosome loss (for more details see [32]).