Evidence for the single phase pairing theory of meiosis.

The segregation pattern of an attached X chromosome with several Y-autosome translocations conflicts with the expectations based on the distributive pairing hypothesis because the chromosomes segregating from the translocation configuration include both exchange and non-exchange chromosomes. The results of the second experiment involving three compound chromosomes go even further; they suggest that the essential association which determines the segregation of nonhomologous elements is in fact set up prior to the time of crossing over.