These translocation lines were generated from homeologous chromosome pairing, or mis-division and reconstruction of univalent chromosomes.
染色体易位有的来源于同祖配对交换,有的来源于单价体错分裂或断裂的重建。
英语百科
Bivalent (genetics)
A bivalent, sometimes referred to as a tetrad, is the association of a pair of homologous chromosomes physically held together by at least one DNA crossover. This physical attachment allows for alignment and segregation of the homologous chromosomes in the first meiotic division.