The transmission of FISH-painted patterns derived from complex chromosome exchanges.

The first 26 families of complex chromosome-type exchanges (from three breaks in two chromosomes to five breaks in five chromosomes) have been evaluated, and the 15,060 exchanges resulting from unrestricted restitution or rejoining of the break ends yields 203 distinctive patterns, if a single participating chromosome is FISH-painted. If we assume that any exchange that produces an acentric fragment of any sort (compound-terminal or interstitial) will be ultimately eliminated in a continuously dividing cell population, then, irrespective of family origin, only 17 of these patterns (approximately 8%) will be transmitted, long-term. The 17 are illustrated, and the implications briefly discussed.